#### 12th Standard Maths English Medium Free Online Test 1 Mark Questions 2020 - Part Four

12th Standard

Reg.No. :
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Maths

Time : 00:10:00 Hrs
Total Marks : 10

10 x 1 = 10
1. The augmented matrix of a system of linear equations is $\left[ \begin{matrix} 1 \\ \begin{matrix} 0 \\ 0 \end{matrix} \end{matrix}\begin{matrix} 2 \\ \begin{matrix} 1 \\ 0 \end{matrix} \end{matrix}\begin{matrix} 7 \\ \begin{matrix} 4 \\ \lambda -7 \end{matrix} \end{matrix}\begin{matrix} 3 \\ \begin{matrix} 6 \\ \mu +5 \end{matrix} \end{matrix} \right]$. The system has infinitely many solutions if

(a)

λ = 7, μ ≠ -5

(b)

λ = 7, μ = 5

(c)

λ ≠ 7, μ ≠ -5

(d)

λ = 7, μ = -5

2. If |z1|=1,|z2|=2|z3|=3 and |9z1z2+4z1z3+z2z3|=12, then the value of |z1+z2+z3| is

(a)

1

(b)

2

(c)

3

(d)

4

3. When the eccentricity of a ellipse becomes zero, then it becomes a

(a)

straight line

(b)

circle

(c)

point

(d)

parabola

4. The angle between the lines $\frac { x-2 }{ 3 } =\frac { y+1 }{ -2 }$, z=2 and $\frac { x-1 }{ 1 } =\frac { 2y+3 }{ 3 } =\frac { z+5 }{ 2 }$

(a)

$\frac{\pi}{6}$

(b)

$\frac{\pi}{4}$

(c)

$\frac{\pi}{3}$

(d)

$\frac{\pi}{2}$

5. The number given by the Mean value theorem for the function $\cfrac { 1 }{ x }$,x∈[1,9] is

(a)

2

(b)

2.5

(c)

3

(d)

3.5

6. Linear approximation for g(x) = cos x at x=$\frac{-\pi}{2}$ is

(a)

x + $\frac{-\pi}{2}$

(b)

- x + $\frac{\pi}{2}$

(c)

x - $\frac{\pi}{2}$

(d)

- x + $\frac{\pi}{2}$

7. The degree of the differential equation y $y(x)=1+\frac { dy }{ dx } +\frac { 1 }{ 1.2 } { \left( \frac { dy }{ dx } \right) }^{ 2 }+\frac { 1 }{ 1.2.3 } { \left( \frac { dy }{ dx } \right) }^{ 3 }+....$ is

(a)

2

(b)

3

(c)

1

(d)

4

8. The solution of $\frac{dy}{dx}+y$ cot x=sin 2x is

(a)

y sin x=$\frac{2}{3}$sin3x+c

(b)

y sec x=$\frac{x^2}{2}+c$

(c)

y sin x =c+x

(d)

2y sin x=sin x-$\frac{sin\ 3x}{3}+c$

9. In the set Q define a⊙b= a+b+ab. For what value of y, 3⊙(y⊙5)=7?

(a)

y=$\frac{2}{3}$

(b)

y=$\frac{-2}{3}$

(c)

y=$\frac{-3}{2}$

(d)

y=4

10. Which of the following is a contradiction?

(a)

p v q

(b)

p ∧ q

(c)

q v ~ q

(d)

q ∧ ~ q