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: 01/06/2021
QB365 provides detailed and simple solution for every book back questions in class 12 Maths subject.It will helps to get more idea about question pattern in every book back questions with solution.
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 Test1.
If α and β are the roots of the quadratic equation 2x2−7x+13 = 0 , construct a quadratic equation whose roots are α2 and β2.
2.
If α and β are the roots of the quadratic equation 17x2+43x−73 = 0 , construct a quadratic equation whose roots are α + 2 and β + 2.
3.
Solve the equation x3- 5x2- 4x + 20 = 0
4.
If α, β and γ are the roots of the cubic equation x3+2x2+3x+4 = 0, form a cubic equation whose roots are, 2α, 2β, 2γ
5.
If the sides of a cubic box are increased by 1, 2, 3 units respectively to form a cuboid, then the volume is increased by 52 cubic units. Find the volume of the cuboid.
6.
Find the roots of 2x3 + 3x2 + 2x + 3 = 0
7.
Solve the equation
2x3 - 9x2 + 10x = 3
8.
Solve the equation 3x3-26x2+52x - 24 = 0 if its roots form a geometric progression.
9.
Solve the equation 9x3- 36x2+ 44x -16 = 0 if the roots form an arithmetic progression.
10.
Find the sum of squares of roots of the equation 2x4- 8x3+ 6x2-3 = 0.
1.
Since α and β are the roots of the quadratic equation, we have α + β =\(\frac { 7 }{ 2 } \) and αβ = \(\frac { 13 }{ 2 } \).
Thus, to construct a new quadratic equation,
Sum of the roots = α2+β2 = (α+β)2-2αβ =\(\frac { -3 }{ 4 } \)
Product of the roots = α2β2 = (αβ)2 = \(\frac { 169 }{ 4 }\)
Thus a required quadratic equation is x2+\(\frac { 3 }{ 4 } x+\frac { 169 }{ 4 } \)= 0.
From this we see that 4x2+3x+169 = 0 is a quadratic equation with roots α2 and β2.
2.
Since α and β are the roots of 17x2+ 43x −73 = 0 , we have α + β =\(\frac { -43 }{ 17 } \) and αβ =\(\frac { -73 }{ 17 } \).
We wish to construct a quadratic equation with roots α + 2 and β + 2. Thus, to construct such a quadratic equation, calculate
the sum of the roots = α + β + 4 = \(\frac { -4 }{ 17 } +4=\frac { 25 }{ 17 } \) and
the product of the roots = αβ + 2(α+β)+4 = \(\frac { -73 }{ 17 } +2\left( \frac { -43 }{ 17 } \right) +4=\frac { -91 }{ 17 } \)
Hence a quadratic equation with required roots is x2-\(\frac { 25 }{ 17 } x-\frac { 91 }{ 17 } \) = 0
Multiplying this equation by 17, gives 17x2−25x−91 = 0
which is also a quadratic equation having roots α + 2 and β + 2
3.
If P(x) denotes the polynomial in the equation, then P(2) = 0.
Hence 2 is a root of the polynomial.
To find other roots, we divide the given polynomial x3−5x2−4x + 20 by x − 2 and get Q(x) = x2 −3x−10 as the quotient.
Solving Q(x) = 0 we get −2 and 5 as roots.
Thus 2, −2, 5 are the solutions of the given equation.
4.
The roots of x3+2x2+3x+4 = 0 are ∝, β, ૪
∴ ∝+β+૪ = -co-efficient of x2 = -2 ...(1)
∝β + β૪ + ૪∝ = co-effficient of x = 3 ....(2)
-∝β૪ = +4 ⇒ ∝β૪ = -4 ...(3)
Form a cubic equation whose roots are 2∝, 2β, 2૪
2∝+2β+2૪ = 2(∝+β+૪) = 2(-2) = -4 [from (1)]
4∝β+4β૪+4૪∝ = 4(∝β+β૪+୪∝) = 4(3) = 12 [from (2)]
(2∝)(2β)(2૪) = 8(∝β૪) = 8(-4) = -32 [from (3)]
∴ The required cubic equation is
x3-(2∝+2β+2૪)x2 + (2∝β+2β૪+2୪∝)x - (2∝)(2β)(2૪) = 0
⇒ x3+(-4)x2+12x+32 = 0
⇒ x3+4x2+12x+32 = 0
5.
The length and breadth of the cuboid are x + 1.
x + 2 and x + 3
[∵ they are increased by 1, 2, 3 units]
Also volume = V + 52 .
[since V is increased by 52]
∴ V + 52 = (x +1)(x + 2)(x + 3) .........(1)
⇒ V = (x + 1) (x + 2) (x + 3) - 52
Here a = -1, β = -2, ૪ = -3
⇒ V = x3-x2(α+β+૪)+x(αβ+β૪+૪α)-αβ૪ = 52
⇒ V = x3-x2(-1-2-3)+x(2+6+3)-(-1)(-2)(-3) = 52
⇒ V = x3-x2(-6)+x(11)+6-52
⇒ x3 = x2+6x2+11x+6-52
⇒ 6x2+11x-46 = 0
⇒ (6x+23)(x-2) = 0
⇒ (6x+23)(x-2) = 0
⇒ x = 2

∴ Volume of the cube = x3 = 23 = 8.
Volume of a cuboid = 52 + 8 = 60
[∵ x = \(\frac{-23}{6}\) is not possible as x represents the side of the cube]
6.
According to our notations, an= 2 and a0 = 3.
If \(\frac{p}{q}\) is a zero of the polynomial, then as (p, q) = 1, p must divide 3 and q must divide 2.
Clearly, the possible values of p are 1, −1, 3, −3 and the possible values of q are 1, −1, 2, −2.
Using these p and q we can form only the fractions \(\pm \frac { 1 }{ 1 } ,\pm \frac { 1 }{ 2 } ,\pm \frac { 3 }{ 2 } ,\pm \frac { 3 }{ 1 } \).
Among these eight possibilities, after verifying by substitution, we get \(\frac { -3 }{ 2 } \) is the only rational zero.
To find other roots, we divide the given polynomial 2x3+ 3x2+ 2x + 3 by 2x + 3 and get x2+1 as the quotient with zero remainder. Solving x2+1 = 0, we get i and −i as roots. Thus \(\frac { -3 }{ 2 } \), -i, i are the roots of the given polynomial equation.
7.
Since the sum of the co-efficients is
2 - 9 + 10 - 3 = 12 - 12 = 0
⇒ x = 1 is a root of (x)
∴ (x - 1) is a factor of (x)
To find the other factor, let us divide f(x) by x-1

[Using synthetic division]
f(x) = (x-1)(x - 3)(2x - 1) = 0
⇒x - 1 = 0, x - 3 = 0 or 2x - 1 = 0
⇒ x = 1, x = 3x, x = \(\frac{1}{2}\)
Hence the roots are 1, 3, \(\frac{1}{2}\).
8.
Let the roots form a GP be \(\frac{a}{\lambda}\), a, a\(\lambda\)
Product of the roots \(\frac{a}{\lambda} \times a \times a \lambda=\frac{24}{3}=8\)
a3 = 8
a = 2
Sum of the roots, \(\frac{a}{\lambda}+a+a \lambda=\frac{26}{3}\)
\( a\left(\frac{1}{\lambda}+1+\lambda\right) =\frac{26}{3} \)
\(2\left(\frac{1+\lambda+\lambda^{2}}{\lambda}\right) =\frac{26}{3} \)
\( 3+3 \lambda+3 \lambda^{2} =13 \lambda \)
\(3 \lambda^{2}+3 \lambda-13 \lambda+3 =0 \)
\(3 \lambda^{2}-10 \lambda+3 =0\)
\( (\lambda-3)(3 \lambda-1)=0 \)
\( \lambda=3 \text { (or) } \lambda=\frac{1}{3}\)
\( \lambda=3, \quad \frac{a}{\lambda}=\frac{2}{3} , \)
\( a \lambda=2(3)=6 \)
If \( \lambda=\frac{1}{3}, \frac{a}{\lambda}=\frac{2}{\frac{1}{3}}=6 \)
If \( a \lambda=2\left(\frac{1}{3}\right)=\frac{2}{3} \)
Roots are \(\frac{a}{\lambda},\ a,\ a \lambda\)
If \(\lambda\) = 3 roots are \(\frac{2}{3}\), 2, 6
If \(\lambda=\frac{1}{3}\) roots are 6, 2, \(\frac{2}{3}\)
9.
Here, a = 9, b = - 36, c = 44, d = -16
Since the roots form an arithmetic progression,
Let the roots be a - d, a and a + d
Sum of the roots \(=\frac { -b }{ a } \)
\(\Rightarrow (a-d)+(a)+(a+d)=\frac { -(-36) }{ 9 } =4\)
\(\Rightarrow 3a=4\Rightarrow a=\frac { 4 }{ 3 } \)
and product of the roots \(=\frac { -d }{ a } \)
\(=\frac { -(-16) }{ 9 } =\frac { 16 }{ 9 } \)
\(\Rightarrow (a-d)(a)(a+d)=\frac { 16 }{ 9 } \)
\(\left( { a }^{ 2 }-{ d }^{ 2 } \right) (a)=\frac { 16 }{ 9 } \)
\(\left( \frac { 16 }{ 9 } -{ d }^{ 2 } \right) \left( \frac { 4 }{ 3 } \right) =\frac { 16 }{ 9 } \ [\because a=\frac { 4 }{ 3 } ]\)
\(\frac { 16 }{ 9 } -{ d }^{ 2 }=\frac { 16 }{ 9 } \times \frac { 3 }{ 4 } =\frac { 4 }{ 3 } \)
\(\frac { 16 }{ 9 } -\frac { 4 }{ 3 } ={ d }^{ 2 }=\frac { 16 }{ 9 } \times \frac { 3 }{ 4 } =\frac { 4 }{ 3 } \)
\(\frac { 16 }{ 9 } -\frac { 4 }{ 3 } ={ d }^{ 2 }\)
\(\Rightarrow { d }^{ 2 }=\frac { 16-12 }{ 9 } =\frac { 4 }{ 9 } \)
\(\Rightarrow d=\pm \sqrt { \frac { 4 }{ 9 } } =\frac { 2 }{ 3 } \)
∴ The roots are a-d, a, a+d
\(\Rightarrow \frac { 4 }{ 3 } -\frac { 2 }{ 3 } ,\frac { 4 }{ 3 } ,\frac { 4 }{ 3 } +\frac { 2 }{ 3 } \Rightarrow \frac { 2 }{ 3 } ,\frac { 4 }{ 3 } ,2\)
10.
Given equation is 2x4- 8x + 6x2- 3 = 0
Here a = 2, b = -8, c = 6, d = 0, e = -3
Let ∝, β, ૪ and \(\delta \) be the roots of equation (1)
Then by Vieta's formula,
\(\sum { _{ 1 }= } \alpha +\beta +\gamma +\delta =\frac { -b }{ a } =\frac { -(-8) }{ 2 } =4\)
\(\sum { _{ 2 } } =\alpha \beta +\alpha \gamma +\alpha \delta +\beta \gamma +\beta \delta +\gamma \delta =\frac { c }{ a } =\frac { 6 }{ 2 } =3\)
\(\sum { _{ 3 } } =\alpha \beta \gamma +\alpha \beta \delta +\alpha \gamma \delta +\beta \gamma \delta =\frac { -d }{ a } =\frac { 0 }{ a } \)
\(\sum { _{ 4 } } =\alpha \beta \gamma \delta =\frac { e }{ a } =\frac { -3 }{ 2 } \)
Now, (a+b+c+d)2 = a2+b2+c2+d2+2(ab+ac+ad+bc+cd)
⇒ n∝2+β2+૪2+\(\delta\)2 = (∝ + β + ૪ + \(\delta\))2-2(\(\alpha \beta +\alpha \gamma +\alpha \delta +\beta \gamma +\beta \delta +\gamma \delta \))
∝2 + β2 + ૪2 = 42-2(3) = 16 - 6 = 10
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