MCQ
If ${\left( {{2 \over 3}} \right)^{x + 2}} = {\left( {{3 \over 2}} \right)^{2 - 2x}},$then $x =$
  • A
    $1$
  • B
    $3$
  • $4$
  • D
    $0$

Answer

Correct option: C.
$4$
c
(c) ${\left( {{2 \over 3}} \right)^{x + 2}} = {\left( {{3 \over 2}} \right)^{2 - 2x}}$ ==> ${\left( {{2 \over 3}} \right)^{x + 2}} = {\left( {{2 \over 2}} \right)^{2 - 2x}}$.

Clearly $x + 2 = 2x - 2$ ==> $x = 4$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

In a certain test ${a_i}$ students gave wrong answers to at least $i$ questions where $i = 1,\;2,\;3,\;......k$. No student gave more than $k$ wrong answers. The total numbers of wrong answers given is
Let $f(x)=\sin \left(\frac{\pi}{6} \sin \left(\frac{\pi}{2} \sin x\right)\right)$ for all $x \in R$ and $g(x)=\frac{\pi}{2} \sin x$ for all $x \in R$. Let (f० g)(x) denote $f(g(x))$ and $(g \circ f)(x)$ denote $g(f(x))$. Then which of the following is (are) true ?

$(A)$ Range of $f$ is $\left[-\frac{1}{2}, \frac{1}{2}\right]$

$(B)$ Range of $f \circ g$ is $\left[-\frac{1}{2}, \frac{1}{2}\right]$

$(C)$ $\lim _{x \rightarrow 0} \frac{f(x)}{g(x)}=\frac{\pi}{6}$

$(D)$ There is an $x \in R$ such that $( g \circ f )(x)=1$

Let $S = \left\{ {\left( {x,y} \right) \in {R^2}:\frac{{{y^2}}}{{1 + r}} - \frac{{{x^2}}}{{1 - r}} = 1} \right\}$, where $r \ne \pm 1$. Then $S$ represents
If $1+\frac{1+2}{2}+\frac{1+2+3}{3}+\ ....$ to n terms is S, then S is equal to:
If ${x^2} + px + 1$ is a factor of the expression $a{x^3} + bx + c$, then
Equation of the hour hand at $4$ O’ clock is
Let $y = f(x) = ax^2 + 2bx + c,$ (where $a, b, c \in  R$ and $a \neq 0)$ if $f(x) = 0$ has imaginary roots and $4a + 4b + c < 0$ then which of the following is true
The number of integral terms in the expansion of $\left(3^{\frac{1}{2}}+5^{\frac{1}{4}}\right)^{680}$ is equal to
Period of $|\sin 2x|$ is
The number of ways in which $3$ children can distribute $10$ tickets out of $15$ consecutively numbered tickets themselves such that they get consecutive blocks of $5, 3 $ and $2$ tickets is