List of practice Questions

If \( A = \left[ \begin{array}{cc} \alpha & 2 \\ 1 & 2 \end{array} \right] \), \( B = \left[ \begin{array}{cc} 1 & 1 \\ 1 & 1 \end{array} \right] \) and \( A^2 - 4A + 2I = 0, B^2 - 2B + I = 0 \), then \( \text{adj}(A^3 - B^3) \) is equal to

Area enclosed by \[ x^2 + 4y^2 \leq 4, \quad |x| \leq 1, \quad y \geq 1 - |x| \text{ is} \]

The value of \[ \int_0^{\frac{\pi}{2}} \left( \sin x + \sin 2x + \sin 3x \right) dx \] is

If \( x^2 + x + 1 = 0 \), then \[ \left( x + \frac{1}{x} \right)^4 + \left( x^2 + \frac{1}{x^2} \right)^4 + \left( x^3 + \frac{1}{x^3} \right)^4 + \dots + \left( x^{25} + \frac{1}{x^{25}} \right)^4 \] is

If \( a_1, a_2, a_3, \dots \) are the terms of an increasing geometric progression such that \[ a_1 + a_3 + a_5 = 21, \quad a_1a_3a_5 = 64 \] then \[ a_1 + a_2 + a_3 \] is

Consider the following statements:
(A) Propanal and Propanone are functional isomers.
(B) Ethoxyethane and methoxypropane are metameres.
(C) But-2-ene shows optical isomerism.
(D) But-1-ene and But-2-ene are functional isomers.
(E) Pentane and 2, 2-dimethylpropane are chain isomers.
In the light of the above statements, choose the correct option.

Given below are two statements:
Statement I: When electric discharge is put on hydrogen, it emits discrete frequency in the electromagnetic spectrum.
Statement II: Frequency of He\(^+\) ion of 2\(^\text{nd}\) line of Balmer series is equal to first line of Lyman series.
In the light of the above statements, choose the correct option.

C₆H₁₂O₃ gives positive iodoform test on hydrolysis with dil. Acid. The hydrolysis product formed gives Tollens’ and iodoform test both. Find structure of C₆H₁₂O₃.

Consider the following reaction:
\[ \text{Ca} + 2\text{HCl} \rightarrow \text{CaCl}_2 + \text{H}_2 \]
\text{We have 14 g Ca reacts with excess of HCl. Choose the incorrect option.}

Let $5000<N<9000$ and $N$ has digits from the set $\{0,1,2,5,9\}$. If digits can be repeated, then find the number of such numbers $N$ which are divisible by $3$.

If $A=\{1,2,3,4\}$. A relation from set $A$ to $A$ is defined as $(a,b)\,R\,(c,d)$ such that $2a+3b=3c+4d$. Find the number of elements in the relation.

$2.8 \times 10^{-3}$ mol of CO$_2$ is left after removing $10^{21}$ molecules from its $x$ mg sample. The mass of CO$_2$ taken initially is: Given: $N_A = 6.02 \times 10^{23}\,\text{mol}^{-1}$

If matrices \( A \) and \( B \) are such that \[ A = \begin{bmatrix} 0 & -2 & 3 \\ -2 & 0 & 1 \\ -1 & 1 & 0 \end{bmatrix} \] and \( B(I - A) = (I + A) \), then find \( B \).

Evaluate the limit: \[ \lim_{x \to 0} \frac{e^{x}\left(e^{\tan x - x} - 1\right) + \ell n(\sec x + \tan x) - x}{\tan x - x} \]

Let \[ f(x)=\int \frac{1-\sin(\ell n t)}{1-\cos(\ell n t)} \, dt \] and \[ f\left(e^{\pi/2}\right)=-e^{\pi/2} \] then find $f\left(e^{\pi/4}\right)$.

Let the mean and variance of 10 numbers be $10$ and $2$ respectively. If one number $\alpha$ is replaced by another number $\beta$, then the new mean and variance are $10.1$ and $1.99$ respectively. Find $(\alpha+\beta)$.

The value of \[ \frac{\sqrt{3}\,\cosec 20^\circ-\sec 20^\circ}{\cos 20^\circ \cos 40^\circ \cos 60^\circ \cos 80^\circ} \] is:

$A_1$ is the area bounded by $y=x^2+2$, $x+y=8$, and the $y$-axis in the first quadrant, and $A_2$ is the area bounded by $y=x^2+2$, $y^2=x$, $x=0$ and $x=2$ in the first quadrant. Find $(A_1-A_2)$.

Evaluate the series \[ \frac{1}{25!}+\frac{1}{3!\,23!}+\frac{1}{5!\,21!}+\cdots \text{ up to 13 terms.} \]

If $\cot x=\dfrac{5}{12}$ for some $x\in\left(\pi,\dfrac{3\pi}{2}\right)$, then \[ \sin 7x\left(\cos\frac{13x}{2}+\sin\frac{13x}{2}\right) +\cos 7x\left(\cos\frac{13x}{2}-\sin\frac{13x}{2}\right) \] is equal to:

Find the number of real solutions of \[ x|x-3|+|x-1|+3=0 \]

Consider a geometric sequence $729,\,81,\,9,\,1,\ldots$ If $P_n$ denotes the product of first $n$ terms of the G.P. such that \[ \sum_{n=1}^{40} (P_n)^{\frac{1}{n}}=\frac{3^{\alpha}-1}{2\times 3^{\beta}}, \] then find the value of $(\alpha+\beta)$.

Consider an A.P. $a_1,a_2,\ldots,a_n$ with $a_1>0$, $a_2-a_1=-\dfrac{3}{4}$ and $a_n=\dfrac{a_1}{4}$. If \[ \sum_{i=1}^{n} a_i=\frac{525}{2}, \] then find $\sum_{i=1}^{17} a_i$.

If the domain of \[ f(x)=\log_{(10x^2-17x+7)}\,(18x^2-11x+1) \] is $(-\infty,a)\cup(b,c)\cup(d,\infty)-\{e\}$, then find $90(a+b+c+d+e)$.