12th Standard Syllabus & Materials
12th Standard
TN 12th Computer Applications மின்னணு தரவு பரிமாற்றம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின் - வணிக பாதுகாப்பு அமைப்புகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின்னணு செலுத்தல் முறைகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின் - வணிகம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications திறந்த மூல கருத்துருக்கள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications வலையமைப்பு வடமிடல் Sample Question Papers Study Material - QB365 Set A

Published on: 20/10/2025
Download Tamil Nadu 12th Standard Maths question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Maths Test

1.
The value of sin-1\((\frac{1}{2})\) + cos-1\((\frac{1}{2})\) is
0
\(\frac{\pi}{2}\)
\(\frac{\pi}{3}\)
\(\pi\)
2.
In 16 throws of a die getting an even number is considered a success, then the variance of the successes is ____________
4
2
6
256
3.
ln which region, the curve y2 (a + x) = x2 (3a - x) does not lie?
x > 0
0 < x < 3
\(x \leq-a \text { and } x>3 a\)
\(-a<x<3 a\)
4.
An asymptote to the curve y2 (a + 2x) = x2 (3a - x) is ____________
x = 3a
\(x=-\frac{a}{2}\)
\(x=\frac{a}{2}\)
x = 0
5.
6.
If \(\vec{a}\) and \(\vec{b}\) include an angle 120o and their magnitude are 2 and \(\sqrt{3}\) then \(\vec{a} .\vec{b}\) is equal to _____________
\(\sqrt{3}\)
\(-\sqrt{3}\)
2
\(-\frac{\sqrt{3}}{2}\)
7.
8.
Give the coordinates of the circle's centre and its radius \((x-2)^{2}+(y+9)^{2}=1\) ___________
(2, -9), r = 1
(- 2, 9), r = 2
(9, 2), r = 1
None of these
9.
If x is a continuous random variable then P(x ≥ a) =
\(P(x \ < \ a)\)
\(P(a\le x\le b)\)
\(P\left( x>a \right) \)
\(1-P\left( x\le a-1 \right) \)
10.
11.
The angle made by any tangent to the curve y = x5 + 8x + 1 with the X-axis is a __________
obtuse
right angle
acute angle
no angle
12.
13.
14.
The angle between the vector \(3\overset { \wedge }{ i } +4\overset { \wedge }{ j } +\overset { \wedge }{ 5k } \) and the z-axis is ___________
30o
60o
45o
90o
15.
If the foci of the ellipse \(\frac { { x }^{ 2 } }{ 16 } +\frac { { y }^{ 2 } }{ { b }^{ 2 } } \) = 1 and the hyperbola \(\frac { { x }^{ 2 } }{ 144 } -\frac { { y }^{ 2 } }{ 81 } =\frac { 1 }{ 25 } \) coincide then b2 is __________
1
5
7
9
16.
If a parabolic reflector is 20 cm in diameter and 5 cm in diameter and 5 cm deep, then its focus is ____________
(0, 5)
(5, 0)
(10, 0)
(0, 10)
17.
\(cot\left( \frac { \pi }{ 4 } -{ cot }^{ -1 }3 \right) \)
7
6
5
none
18.
If ax2 + bx + c = 0, a, b, c \(\in\) R has no real zeros, and if a + b + c < 0, then __________
c>0
c<0
c=0
c≥0
19.
If f(x) = 0 has n roots, then f'(x) = 0 has __________ roots
n
n -1
n+1
(n-r)
20.
The quadratic equation whose roots are ∝ and β is ___________
(x - ∝)(x -β) = 0
(x - ∝)(x + β) = 0
∝ + β = \(\frac{b}{a}\)
∝ β = \(\frac{-c}{a}\)
21.
22.
Suppose X is a binomial variate X ~ B(5, p) and P(X = 2) = P(X = 3), then find p.
23.
If 10 coins are tossed, find the probability that exactly 5 heads appears.
24.
Show that two lines \(\vec{r}=(\hat{i}-\hat{j})+i(2 \hat{i}+\hat{k})\) and \(\vec{r}=(2 \hat{i}-\hat{j})+s(\hat{i}+\hat{j}-\hat{k})\) are skew lines and find the distance between them.
25.
The total revenue received from the sale of x units of a product is given by R(x) = 3x2 + 36x + 5. Find the marginal revenue when x = 5, where by marginal revenue means the rate of change of total revenue.
26.
The probability of success of an event is p and that of failure is q. Find the expected number of trails to get a first success.
27.
Find thc equation of the hyperbola whose foci are (0, \(\pm\)5) and the length of the transverse axis is 6.
28.
Find the value of \(\cos ^{-1}\left(\frac{1}{2}\right)-2 \sin ^{-1}\left(-\frac{1}{2}\right)\)
29.
Prove that the function f(x)=2x2+3x is strictly increasing on \(\left[ -\frac { 1 }{ 2 } ,\frac { 1 }{ 2 } \right] \)
30.
Verify Lagrange’s Mean Value theorem for \(f(x)=\sqrt { x-2 } \) in the interva [2,6]
31.
For the ellipse x2 + 3y2 = a2, find the length of major and minor axis.
32.
For the distribution function given by \(\mathrm{F}(x)= \begin{cases}0, & x<0 \\ x^{2}, & 0 \leq x \leq 1 \\ 1, & x>1\end{cases}\). Find the density function. Also evaluate
\( (i) \ \mathrm{P}(0.5<x<0.75) \)
\(
(ii) \ \mathrm{P}(x \leq 0.5) \)
\(
(iii)\ \mathrm{P}(\mathrm{X}>0.75) \)
33.
The foot of perpendicular drawn from the origin to the plane is (4, -2, -5), find the equation of the Plane.
34.
The co-ordinates of the vertices of a hyperbola are (9, 2) and (1, 2) and the distance between its two foci is 10. Find its equation and also the length of its latus rectum.
35.
Find the equations of directrices, latus rectum and length of latus rectums of the following ellipse \(4 x^{2}+3 y^{2}+8 x+12 y+4=0\)
36.
Solve the equation
\(60 x^{4}-736 x^{3}+1433 x^{2}-736 x+60=0\)
37.
Find the intervals of concavity and the points of inflection of f(x)=12x2-2x3-x4.
38.
Find the angle of intersection of the curves 2y2 = x3 and y2 = 32x.
39.
If \({ tan }^{ -1 }\left( \frac { \sqrt { 1+{ x }^{ 2 } } -\sqrt { 1-{ x }^{ 2 } } }{ \sqrt { 1+{ x }^{ 2 } } +\sqrt { 1-{ x }^{ 2 } } } \right) =a\) than prove that x2 = sin 2a
40.
A player tosses two unbiased coins. He wins Rs. 5 if two heads appear, Rs. 2 if one head appear and Rs. 1 if no head appear. Find the expected amount to win.
41.
If a continuous random variable X has the p.d.f. f(x) = 4x(x-1)3, then find P(1 ≤ X ≤ 2).
42.
Find the magnitude and direction cosines of the moment about the point (0, -2, 3) of a force \(\hat{i}+\hat{j}+\hat{k}\) whose line of action passes though the origin.
43.
If \(\vec{a}, \vec{b}\) are any two vectors, then \(|a \times b|^{2}+(a \cdot b)^{2}=\) \(|\vec{a}|^{2}|\vec{b}|^{2}\)
44.
The side of an equilateral triangle is increasing at the rate of 2 cm / sec. At what rate is its area increasing when the side of the triangle is 20 cm?
45.
Evaluate: \(\lim _{x \rightarrow 0}(\cos x)^{\frac{1}{x}}\)
46.
Find the critical numbers (only x values) of the function \(f(x)=x^{4 / 5}(x-4)^{2}\)
47.
Find the equation of the ellipse whose foci are (1, 3) and (1, 9) and eccentricity is \(\frac{1}{2}\)
48.
Find the equation of the tangent to \(x^{2}+y^{2}-4 x+4 y-8=0 \text { at }(-2,-2)\)
49.
Evaluate \(\sin ^{-1}\left(\sin \left(-600^{\circ}\right)\right)\)
50.
Calculate the sum of the cubes of the roots of \(x^{4}+2 x+3=0\)
1.
(b)
\(\frac{\pi}{2}\)
2.
(a)
4
3.
(c)
\(x \leq-a \text { and } x>3 a\)
4.
(b)
\(x=-\frac{a}{2}\)
5.
(d)
6.
(b)
\(-\sqrt{3}\)
7.
(c)
8.
(a)
(2, -9), r = 1
9.
(c)
\(P\left( x>a \right) \)
10.
(d)
11.
(c)
acute angle
12.
(d)
13.
(c)
14.
(c)
45o
15.
(c)
7
16.
(b)
(5, 0)
17.
(a)
7
18.
(b)
c<0
19.
(b)
n -1
20.
(a)
(x - ∝)(x -β) = 0
21.
22.
Given n = 5 and
P(X = 2) = P(X = 3)
P(X = x) = \(n \mathrm{C}_{x} p^{x} q^{n-x}\)
x = 0, 1, 2,...n
Therefore (1) becomes,
\(
5 \mathrm{C}_{2} p^{2} q^{3} =5 \mathrm{C}_{3} p^{3} q^{2}
\)
\(\Rightarrow \frac{5 \times 4}{1 \times 2} q =\frac{5 \times 4 \times 3}{3 \times 2 \times 1} p \
\)
\(\Rightarrow \text { Since } p+q =p
\)
\(\Rightarrow p+p =1
\)
\(\Rightarrow 2 p =1
\)
\(\Rightarrow p=\frac{1}{2}
\)
23.
Given = 10
\(
\mathrm{P}(\mathrm{H})=\frac{1}{2} \Rightarrow p=\frac{1}{2}
\)
\(\therefore q-1-p \)
\(=1-\frac{1}{2}=\frac{1}{2} \)
\(\mathrm{P}(\mathrm{X}=x)=n \mathrm{C}_{x} p^{x}(1-p)^{n-x} \)
\(x=0,1,2, \ldots n
\)
\(\therefore \mathrm{P}(\mathrm{X}=5)=10 \mathrm{C}_{5} p^{5} q^{5}
\)
\(=10 \mathrm{C}_{5}\left(\frac{1}{2}\right)^{5}\left(\frac{1}{2}\right)^{5}
\)
\(=10 C_{5}\left(\frac{1}{2}\right)^{10}\)
24.
Comparing the given equations with
\( \vec{r}=\vec{a}+s \vec{b} \ \text { and } \ \vec{r}=\vec{c}+t \vec{d} \)
\(\vec{a}=\hat{i}-\hat{j} \quad \vec{b}=2 \hat{i}+\hat{k} \)
\( \vec{c}=2 \hat{i}-\hat{j} \quad \vec{d}=\hat{i}+\hat{j}+\hat{k} \)
\( \vec{c}-\vec{a}=\hat{i} \)
\( \vec{b} \times \vec{d}=\left|\begin{array}{ccc} \hat{i} & \hat{j} & \hat{k} \\ 2 & 0 & 1 \\ 1 & 1 & -1 \end{array}\right| \)
\( = \hat{i}(0-1)-\hat{j}(-2-1)+\hat{k}(2) \)
\(= -\hat{i}+3 \hat{j}+2 \hat{k} \)
\((\vec{c}-\vec{a}) \cdot(\vec{b} \times \vec{d}) =\hat{i}(-\hat{i}+3 \hat{j}+2 \hat{k}) \)
\( =-1 \neq 0\)
They are skew lines
\( |(\vec{c}-\vec{a}) \cdot(\vec{b} \times \vec{d})| =|-1|=1 \)
\(|(\vec{b} \times \vec{d})| =\sqrt{1+9+4}=\sqrt{14} \)
Distance \( =\frac{|(\vec{c}-\vec{a}) \cdot(\vec{b} \times \vec{d})|}{|\vec{b} \times \vec{d}|} \)
\( =\frac{1}{\sqrt{14}} \text { units } \)
25.
\(R(x)=3 x^{2}+36 x+5\)
Marginal Revenue
\(\mathrm{MR}=\frac{d R}{d x}=6 \mathrm{x}+36\)
When x = 5, MR = 6(5) + 36 = 66
26.
The probability distribution
| x | 0 | 1 | 2 | 3 | 4 | ...... | n | ....... |
| P(X = x) | p | k | qp | q2p | q3p | ........ | qn-1p | ....... |
\(
\mathrm{E}(\mathrm{X}) =\sum p \mathrm{x}
\)
\( =1 \cdot \mathrm{p}+2 \cdot \mathrm{qp}+3 \cdot \mathrm{q}^{2} \mathrm{p}+\ldots .+\mathrm{n} \mathrm{q}^{\mathrm{n}-1} \mathrm{p}+\ldots
\)
\(=\mathrm{p}\left(1+2 \mathrm{q}+3 \mathrm{q}^{2}+\ldots . .+\mathrm{nq}^{\mathrm{n}-1}+\ldots \ldots\right)
\)
\( =\mathrm{p}(1-\mathrm{q})^{-2}
\)
\( =\mathrm{p}(\mathrm{p})^{-2}=\frac{p}{p^{2}}=\frac{1}{p}
\)
27.
From the given data the transverse axis is along y-axis and hence the equation is of the form
\(\frac{(y-k)^{2}}{a^{2}}-\frac{(x-h)^{2}}{b^{2}}=1\)
The centre C (h, &) is the midpoint of F1 and F2
\(i.e. C\ is \left(\frac{0+0}{2}, \frac{5-5}{2}\right)=(0,0)
\)
\(F_{1} F_{2}=2 a e=10
\)
The length of the transverse axis = 2a = 6
\(
\Rightarrow a =3 \text { and } e=\frac{5}{3}
\)
\(b^{2} =a^{2}\left(e^{2}-1\right)
\)
\( =9\left(\frac{25}{9}-1\right)=16\)
\(\therefore\) The required equation is \(\frac{y^{2}}{9}-\frac{x^{2}}{16}=1\)
28.
Let \( \cos ^{-1}\left(\frac{1}{2}\right) =y \)
\(\left(\frac{1}{2}\right) =\cos y \)
\(\cos \frac{\pi}{3} =\cos y \)
\(y =\frac{\pi}{3}\)
Let \( \sin ^{-1}\left(-\frac{1}{2}\right) =x \)
\(-\frac{1}{2} =\sin x \)
\(\sin \left(\frac{-\pi}{6}\right) =\sin x \)
\(x =\frac{-\pi}{6} \)
\( \cos ^{-1}\left(\frac{1}{2}\right)-2 \sin ^{-1}\left(-\frac{1}{2}\right) =\frac{\pi}{3}-2\left(-\frac{\pi}{6}\right) \)
\( =\frac{\pi}{3}+\frac{\pi}{3} =\frac{2 \pi}{3} \)
29.
f(x) is strictly increasing \(\left[ -\frac { 1 }{ 2 } ,\frac { 1 }{ 2 } \right] \)
30.
c = 3
31.
Given equation is x2 + 3y2 = a2
\(\div \) a2 we get, \(\frac { { x }^{ 2 } }{ { a }^{ 2 } } +\frac { { y }^{ 2 } }{ \frac { { a }^{ 2 } }{ 3 } } =1\)
Here a2 and b2 = \(\frac{a^2}{3}\) ⇒ b = \(\frac{a}{\sqrt3}\)
Length of major axis is 2a and
Length of minor axis is 2b = \(\frac { 2a }{ \sqrt { 3 } } \times \frac { \sqrt { 3 } }{ \sqrt { 3 } } =\frac { 2a\sqrt { 3 } }{ 3 } \)
32.
\((i)\ \mathrm{P}(0.5<x<0.75)
\)
\(
=\mathrm{F}(0.75)-\mathrm{F}(0.5)=(0.75)^{2}-(0.5)^{2}
\)
\( =0.3125
\)
\((ii) \ \mathrm{P}(\mathrm{X} \leq 0.5)
\)
\( =\mathrm{P}(-\infty<x \leq 0.5)=\mathrm{F}(0.5)-\mathrm{F}(-\infty)
\)
\( =(0.5)^{2}-0=0.25
\)
\((iii) \ \mathrm{P}(\mathrm{X}>0.75)
\)
\( =\mathrm{P}(0.75 \leq x<\infty)=\mathrm{F}(\infty)-\mathrm{F}(0.75)
\)
\( =1-(0.75)^{2}=0.4375
\)
33.
The required plane Passes through the point A(4, -2, -5) and is Perpendicular to \(\overrightarrow{O A}\)
\(\therefore \vec{a}=4 \hat{i}-2 \hat{j}-5 \hat{k} \text { and } \vec{n}=\overrightarrow{O A}=4 \hat{i}-2 \hat{j}-5 \hat{k}\)
The required equation of the plane is \(\vec{r} \cdot \overrightarrow{\mathrm{n}}=\vec{a} \cdot \vec{n}\)
\(\vec{r} \cdot(4 \hat{i}-2 \hat{j}-5 \hat{k})=(4 \hat{i}-2 \hat{j}-5 \hat{k}) \cdot(4 \hat{i}-2 \hat{j}-5 \hat{k})\)
= 16 + 4 + 25
\(\vec{r} \cdot(4 \hat{i}-2 \hat{j}-5 \hat{k})=45\)
Cartesian form:
\((x \hat{i}+y \hat{j}+z \hat{k}) \cdot(4 \hat{i}-2 \hat{j}-5 \hat{k})=45\)
4x -2y -5z = 45
34.
Given vertices are (9, 2) & (1, 2)
A (9, 2), A' (1, 2)
Centre is midpoint of AA'
\(C(h, k)=\left(\frac{9+1}{2}, \frac{2+2}{2}\right)\)
=(5, 2)
AA' = 2a = 8
a = 4
FF' = 2c = 10
c = 5
\(b^{2}=c^{2}-a^{2}\)
= 25 - 16
b2 = 9
The transverse axis is parallel to x axis
Equation of hyperbola \( \frac{(x-h)^{2}}{a^{2}}-\frac{(y-k)^{2}}{b^{2}}=1 \)
\( \frac{(x-5)^{2}}{16}-\frac{(y-2)^{2}}{5}=1 \)
Length of Latus rectum \( =\frac{2 b^{2}}{a}=\frac{2(9)}{4} \)
\( =\frac{9}{2} \text { units } \)
35.
\(
4 x^{2}+3 y^{2}+8 x+12 y+4 =0
\)
\(\left(4 x^{2}+8 x\right)+\left(3 y^{2}+12 y\right)+4 =0
\)
\(4\left(x^{2}+2 x\right)+3\left(y^{2}+4 y\right) =-4
\)
\(4\left\{(x+1)^{2}-1\right\}+3\left\{(y+2)^{2}-4\right\} =-4
\)
\(4(x+1)^{2}+3(y+2)^{2} =12 \)
\(\div \text { by } 12 \Rightarrow \quad \frac{(x+1)^{2}}{3}+\frac{(y+2)^{2}}{4} =1
\)
The major axis is parallel to y axis
\(
a^{2}=4\ \ b=3
\)
\(a=2 \ \ b=\sqrt{3}
\)
\(c^{2}=a^{2}-b^{2}
\)
= 4 - 3
\(c^{2}=1 \) c = 1
\(
a e =1 \Rightarrow 2(e)=1
\)
\(e =\frac{1}{2}
\)
Centre (h, k) = (-1 , -2)
Equation of directrix y \(
=\pm \frac{a}{e}+k
\)
\( =\pm \frac{2}{\frac{1}{2}}-2
\)
\( =\pm 4-2
\)
y = 4 - 2 & y = -4-2
y = 2 & y = -6
Equation of latus rectum
\(
\mathrm{y}=\pm \mathrm{ae}+\mathrm{k}
\)
\( =\pm(2)\left(\frac{1}{2}\right)-2=\pm 1-2
\)
\( y=1-2 \ \ \quad y=-1-2
\)
\( y=-1 \ \ \quad y=-3
\)
Length of latus rectum \(=\frac{2 b^{2}}{a}=\frac{2(3)}{2}=3\)
36.
The equation is type 1 even degree reciprocal equation.
Dividing by x2
\(60 x^{2}-736 x+1433-\frac{736}{x}+\frac{60}{x^{2}}=0\)
\(60\left(x^{2}+\frac{1}{x^{2}}\right)-736\left(x+\frac{1}{x}\right)+1433=0\) ............(1)
Putting \(\mathrm{y}=x+\frac{1}{x} ; \quad \mathrm{y}^{2}-2=x^{2}+\frac{1}{x^{2}}\)
\(\text {(1) } \Rightarrow 60 y^{2}-736 y+1313=0\)
On solving, we get
\( y =\frac{101}{10} \text { or } \frac{13}{6} \)
\(\text {When } y =\frac{101}{10} \)
\(x+\frac{1}{x} =\frac{101}{10}\)
\( \Rightarrow 10 x^{2}-101 x+10 =0 \)
\(\text { i.e., } x =10, \frac{1}{10} \)
Similarly when y \(=\frac{13}{6}\), We get \(x=\frac{3}{2}, \frac{2}{3}\)
Thus the roots of the given equation are
\(10, \frac{1}{10}, \frac{3}{2}, \frac{2}{3}\)
37.
(−∞,−2)concave downward
(−2,1)concave upward
(1,∞)concave downward
Points of inflections are (−2,48),(1,9)
38.
Given 2y2 = x3
⇒ y2 = \(\frac { { x }^{ 3 } }{ 2 } \) ....(1)
⇒ y2 = 32x ...(2)
From (1) & (2),
\(\frac { { x }^{ 3 } }{ 2 } \) = 32x
⇒ x3 = 64x
⇒ x(x2-64) = 0
⇒ x = 0, 8, -8
when x = 0, y = 0
when x = 8, y2= 32(8)
⇒ y = ±16
when x = -8, y2 = 32(-8)
which is not possible
∴ The point are (0, 0) (8, 16) (8, -16)
Differentiating 2y2 = x3, with respect to 'x'
⇒ 4y\(\frac { dy }{ dx } \) = 3x2
⇒ \(\frac { dy }{ dx } =\frac { 3x^{ 2 } }{ 4y } \)
∴ m1 = \(\left( \frac { dy }{ dx } \right) _{ (8,16) }=\frac { 3\times 8\times 8 }{ 4\times 16 } \)= 3
Differentiating y2 = 32x with respect to 'x',
2y\(\frac { dy }{ dx } \) = 32
⇒ \(\frac { dy }{ dx } =\frac { 32 }{ 2y } =\frac { 16 }{ y } \)
∴ m2 =\(\left( \frac { dy }{ dx } \right) _{ (8,16) }=\frac { 16 }{ 16 } \) = 1
Let θ be the angle between the given curves at (8, 16)
∴ tan θ = \(\left| \frac { { m }_{ 1 }-{ m }_{ 2 } }{ 1+{ m }_{ 1 }{ m }_{ 2 } } \right| =\frac { 3-1 }{ 1+3(1) } \)
=\(\frac { 2 }{ 4 } =\frac { 1 }{ 2 } \)
∴ θ = \({ tan }^{ -1 }\left( \frac { 1 }{ 2 } \right) \).
39.
Given \({ tan }^{ -1 }\left( \frac { \sqrt { 1+{ x }^{ 2 } } -\sqrt { 1-{ x }^{ 2 } } }{ \sqrt { 1+{ x }^{ 2 } } +\sqrt { 1-{ x }^{ 2 } } } \right) =a\)
\(\Rightarrow \frac { \left( \sqrt { 1+{ x }^{ 2 } } -\sqrt { 1-{ x }^{ 2 } } \right) \left( \sqrt { 1+{ x }^{ 2 } } +\sqrt { 1-{ x }^{ 2 } } \right) }{ \left( \sqrt { 1+{ x }^{ 3 } } -\sqrt { 1-{ x }^{ 2 } } \right) \left( \sqrt { 1+{ x }^{ 2 } } +\sqrt { 1-{ x }^{ 2 } } \right) } \)
= \(\frac { tan\alpha +1 }{ tan\alpha -1 } \)
\(\Rightarrow \frac { 2\sqrt { 1+{ x }^{ 2 } } }{ -2\sqrt { 1-{ x }^{ 2 } } } =\frac { tan\alpha +1 }{ tan\alpha -1 } \)
\(\Rightarrow \sqrt { \frac { 1-{ x }^{ 2 } }{ 1+{ x }^{ 2 } } } =\frac { 1-tan\alpha }{ 1+tan\alpha } \)
\(\Rightarrow \sqrt { \frac { 1-{ x }^{ 2 } }{ 1+{ x }^{ 2 } } } =\frac { cos\alpha -sin\alpha }{ cos\alpha +sin\alpha } \)
\(\Rightarrow \frac { 1-{ x }^{ 2 } }{ 1+{ x }^{ 2 } } \left( \frac { cos\alpha -sin\alpha }{ cos\alpha +sin\alpha } \right) ^{ 2 }\)
\(\Rightarrow \frac { 1-{ x }^{ 2 } }{ 1+{ x }^{ 2 } } =\frac { 1-sin2\alpha }{ 1+sin2\alpha } \Rightarrow { x }^{ 2 }=sin2\alpha \)
40.
\(
\mathrm{P}(\mathrm{H}) =\mathrm{P}(\mathrm{T})=\frac{1}{2}
\)
\(\mathrm{P}(\mathrm{X}=5) =\mathrm{P}(\mathrm{HH})=\frac{1}{2} \times \frac{1}{2}=\frac{1}{4}
\)
\(\mathrm{P}(\mathrm{X}=2) =\mathrm{P}(\mathrm{HT})+\mathrm{P}(\mathrm{TH}) \)
\( =\frac{1}{2} \times \frac{1}{2}+\frac{1}{2} \times \frac{1}{2}=\frac{1}{2}
\)
\(\mathrm{P}(\mathrm{X}=1) =\mathrm{P}(\mathrm{TT})=\frac{1}{2} \times \frac{1}{2}=\frac{1}{4}
\)
Hence, the probability distribution function is
| x | 1 | 2 | 5 |
| P(X-x) | \( \frac{1}{4} \) | \( \frac{1}{2}\) | \( \frac{1}{4} \) |
\(
\therefore \mathrm{E}(x) =1 \times \frac{1}{4}+2 \times \frac{1}{2}+5 \times \frac{1}{4}
\)
\( =\frac{1}{4}+1+\frac{5}{4}
\)
\( =\frac{1+4+5}{4}=\frac{10}{4}=2.50\)
Hence, the expected money to win is Rs. 2.50.
41.
Given f(x) = 4k (x-1)2, 1 ≤ x ≤ 3.
Since f(x) is a p.d.f\(\int_{1}^{3} f(x) d x=1\)
\( \Rightarrow \int_{1}^{3} 4 k(x-1)^{3} d x =1 \)
\(\Rightarrow 4 k\left[\frac{(x-1)^{4}}{4}\right]_{1}^{3} =1 \)
\(\Rightarrow \ k\left[2^{4}-0^{4}\right] =1 \)
\(\Rightarrow \ 16 k =1 \)
\(\Rightarrow \ k =\frac{1}{16} \)
\(\therefore \mathrm{P}(1 \leq \mathrm{X} \leq 2) =\int_{+1}^{2} f(x) d x \)
\(\Rightarrow \ =\int_{1}^{2} \frac{1}{4}(x-1)^{3} d x \)
\(\Rightarrow 1{ }^{2} =\frac{1}{4}\left[\frac{(x-1)^{4}}{4}\right]_{1}^{2} \)
\( =\frac{1}{16}\left(1^{4}-0^{4}\right)=\frac{1}{16} \)
42.
Let A be the point (0, -2, 3)
\(
\overrightarrow{\mathrm{r}} =\overrightarrow{\mathrm{OA}}=-2 \hat{\mathrm{j}}+3 \hat{\mathrm{k}}
\)
\(\overrightarrow{\mathrm{F}} =\hat{\mathrm{i}}+\hat{\mathrm{j}}+\hat{\mathrm{k}}
\)
\(\overrightarrow{\mathrm{t}} =\overrightarrow{\mathrm{r}} \times \vec{F}=\left|\begin{array}{lll}
\hat{\mathrm{i}} \hat{\mathrm{j}} & \hat{\mathrm{k}} \\
0 & 2 & 3 \\
1 & 1 & 1
\end{array}\right|
\)
\( =\hat{\mathrm{i}}(-2-3)-\hat{\mathrm{j}}(0-3)+\hat{\mathrm{k}}(0+2)
\)
\(\overrightarrow{\mathrm{t}} =-5 \hat{\mathrm{i}}+3 \hat{\mathrm{j}}+2 \hat{\mathrm{k}}\)
Magnitude of moment \(=\sqrt{(25)+(9)+(4)}=\sqrt{38}\)
Direction cosines \(=\left(\frac{-5}{\sqrt{38}}, \frac{3}{\sqrt{38}}, \frac{2}{\sqrt{38}}\right)\)
43.
Let \(\theta\) be the angle between \(\vec{a}\ and\ \vec{b}\)
\(
\therefore \vec{a} \times \vec{b} =|\vec{a}||\vec{b}| \sin \theta \hat{n}
\)
\(|\vec{a} \times \vec{b}|^{2} =|\vec{a}||\vec{b}| \sin \theta
\)
\(|\vec{a} \times \vec{b}|^{2} =|\vec{a}|^{2}|\vec{b}|^{2} \sin ^{2} \theta
\)
\((\vec{a} \cdot \vec{b})^{2} =|\vec{a}|^{2}|\vec{b}|^{2} \cos ^{2} \theta
\)
\(|\vec{a} \times \vec{b}|^{2}+(\vec{a} \cdot \vec{b})^{2} =|\vec{a}|^{2}|\vec{b}|^{2}\left(\sin ^{2} \theta+\cos ^{2} \theta\right)
\)
\( =|\vec{a}|^{2}|\vec{b}|^{2}
\)
44.
Let 'x' cm be the length of a side of an equilateral triangle and 'A' be its area
\( \mathbf{A} =\frac{\sqrt{3}}{4} x^{2} \)
\(\frac{d A}{d t} =\frac{\sqrt{3}}{2} x \cdot \frac{d x}{d t} \quad\left[\because \frac{d x}{d t}=2\right] \)
\({\left[\frac{d A}{d t}\right]_{x=20} } =\frac{\sqrt{3}}{2}(20)(2)=20 \sqrt{3}\)
Area is increasing at the rate of \(20 \sqrt{3} \mathrm{~cm}^{2} / \mathrm{sec}\)
45.
\( \lim _{x \rightarrow 0}(\cos x)^{\frac{1}{x}} \) \(\left[1^{\infty}\right. \) form
\(\text {Let } y =(\cos x)^{\frac{1}{x}} \)
\(\log y =\frac{1}{x} \log \cos x \)
\(\lim _{x \rightarrow 0} \log y =\lim _{x \rightarrow 0} \frac{\log \cos x}{x}\) \(\left[\frac{0}{0}\right. \) form
Applying L' Hopital's rule
\( =\lim _{x \rightarrow 0}-\frac{\sin x}{\frac{\cos x}{1}} \)
\( =\lim _{x \rightarrow 0}-\tan x=0 \)
\(\therefore \log \left(\lim _{x \rightarrow 0} y\right) =0 \)
\(\lim _{x \rightarrow 0} y =e^{0}=1 \)
\(ie., \lim _{x \rightarrow 0}(\cos x)^{\frac{1}{x}}=1\)
46.
Given \(
f(x) =x^{4 / 5}(x-4)^{2}
\)
\(f^{\prime}(x) =\frac{4}{5} x^{-1 / 5}(x-4)^{2}+x^{4 / 5} 2(x-4)
\)
\( =\frac{4(x-4)^{2}}{5 x^{1 / 5}}+2 x^{4 / 5}(x-4)
\)
\( =\frac{(x-4)}{5 x^{1 / 5}}(4 x-16+10 x)
\)
\(f^{\prime}(x) =\frac{(x-4)}{5 x^{1 / 5}}(14 x-16)
\)
\(f^{\prime}(x) =0 \Rightarrow \mathrm{x}=4, \frac{8}{7}\)
f'(x) does not exists at x = 0
Critical numbers are 0, 4, \(\frac{8}{7}\)
47.
From the given data the major axis is parallel to y axis.
\(\therefore\) The equation is of the form
\(\frac{(x-h)^{2}}{b^{2}}+\frac{(y-k)^{2}}{a^{2}}=1\)
The centre of the ellipse is midpoint of F1, F2
C is \( \left(\frac{1+1}{2}, \frac{3+9}{2}\right) =(1,6) \)
\(F_{1} F_{2} =2 a e=6 \)
\(a e =3 \)
But \( e =\frac{1}{2} \therefore a=6 \)
\(b^{2} =a^{2}\left(1-e^{2}\right)=36\left(1-\frac{1}{4}\right) =27 \)
Thus the required equation is \(\frac{(x-1)^{2}}{27}+\frac{(y-6)^{2}}{36}=1\)
48.
The equation of the tangent at (x1, y1) to the given circle is
\(
x x_{1}+y y_{1}-4\left(\frac{x+x_{1}}{2}\right)+4\left(\frac{y+y_{1}}{2}\right)-8=0
\)
\( x x_{1}+y y_{1}-2\left(x+x_{i}\right)+2\left(y+y_{1}\right)-8=0
\)
At (1, -2), the equation of the tangent is
-2x - 2y - 2(x - 2) + 2(y - 2) - 8 = 0
\(\Rightarrow\) -4x - 8 = 0
\(\Rightarrow\) x + 2 = 0 is the required equation of the tangent.
49.
We have
\(
\sin ^{-1} \left(\sin \left(-600^{\circ}\right)\right)=\sin ^{-1}\left[-\sin \left(600^{\circ}\right)\right]
\)
\( =\sin ^{-1}\left[-\sin \left(360^{\circ}+240^{\circ}\right)\right]=\sin ^{-1}\left(-\sin 240^{\circ}\right)
\)
\(=\sin ^{-1}\left[-\sin \left(180^{\circ}+60^{\circ}\right)\right]
\)
\( =\sin ^{-1}\left[\left(+\sin 60^{\circ}\right)\right]
\)
\( =\sin ^{-1}\left(\sin 60^{\circ}\right)=60^{\circ}
\)
50.
Let the given equation be
\(x^{4}+P_{1} x^{3}+P_{2} x^{2}+P_{3} x+P_{4}=0\)
Here P1 = P2 = 0, P3 = 2 and P4 = 3
By Newton's theorem, \(S_{3}+S_{2} P_{1}+S_{1} P_{2}+3 P_{3}=0\)
\(\text { i.e., } \mathrm{S}_{3}+0+0+3.2=0 \)
\(\Rightarrow \mathrm{S}_{3}=-6 \)
i.e., sum of the cubes of the roots of \(x^{4}+2 x+3=0\) is -6
12th Standard Syllabus & Materials
12th Standard
TN 12th Computer Applications களப்பெயர் முறைமை (DNS) Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications வலையமைப்பு எடுத்துக்காட்டுகள் மற்றும் நெறிமுறைகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications கணினி வலையமைப்பு ஓர் அறிமுகம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications PHP-உடன் MySQL-ஐ இணைத்தல் Sample Question Papers Study Material - QB365 Set A
Tamilnadu Stateboard 12th Standard Subjects

Maths

Chemistry

Physics

Biology

Computer Science

Business Maths and Statistics

Economics

Commerce

Accountancy

History

Computer Applications

Biology

Computer Technology

Computer Applications

Computer Science

Business Maths and Statistics

Commerce

Economics

Maths

Chemistry

Physics

Computer Technology

History

Accountancy

Tamil

English

French
Tamilnadu Stateboard Standards