MCQ
If $y = a{e^{mx}} + b{e^{ - mx}}$, then ${{{d^2}y} \over {d{x^2}}} - {m^2}y = $
  • A
    ${{m}^{2}}(a{{e}^{mx}}-b{{e}^{-mx}})$
  • B
    $1$
  • $0$
  • D
    None of these

Answer

Correct option: C.
$0$
c
(c) $y = a{e^{mx}} + b{e^{ - mx}};$ 

$\therefore \frac{{dy}}{{dx}} = am{e^{mx}} - mb{e^{ - mx}}$

Again $\frac{{{d^2}y}}{{d{x^2}}} = a{m^2}{e^{mx}} + {m^2}b{e^{ - mx}}$

==> $\frac{{{d^2}y}}{{d{x^2}}} = {m^2}(a{e^{mx}} + b{e^{ - mx}}) \Rightarrow \frac{{{d^2}y}}{{d{x^2}}} = {m^2}y$

or $\frac{{{d^2}y}}{{d{x^2}}} - {m^2}y = 0$.

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

The points with position vectors $60i + 3j, 40i − 8j$ and $ai − 52j$ are collinear if:
Domain of function $f(x) = log|5{x} - 2x|$ is $x \in R - A$, then $n(A)$ is (where $\{.\}$ denotes fractional part function)
Choose the correct answer from the given four options.
If A and B are two events and $\text{A}\neq\phi,\text{B}\neq\phi,$ then:
The value of $\left|\begin{array}{lll}(a+1)(a+2) & a+2 & 1 \\ (a+2)(a+3) & a+3 & 1 \\ (a+3)(a+4) & a+4 & 1\end{array}\right|$ is 
Let $f$ be a differentiable function satisfying $f ( x )=\frac{2}{\sqrt{3}} \int_{0}^{\sqrt{3}} f \left(\frac{\lambda^{2} x }{3}\right) d \lambda, x >0$ and $f (1)=\sqrt{3}$. If $y=f(x)$ passes through the point $(\alpha, 6)$, then $\alpha$ is equal to $.........$
Let $A + 2B =$ $\left[ {\begin{array}{*{20}{c}}1&2&0\\6&{ - 3}&3\\{ - 5}&3&1 \end{array}} \right]$ and $2A - B =$ $\left[ {\begin{array}{*{20}{c}}2&{ - 1}&5\\ 2&{ - 1}&6\\0&1&2\end{array}} \right]$ then $Tr (A) - Tr (B)$ has the value equal to
The area bounded by the curves $\text{y}=\sin\text{x},\text{y}=\cos\text{x}\ y −$ axes in first quadrant is:
If $f(x) = \left\{ \begin{array}{l}\frac{{{x^2} + 3x - 10}}{{{x^2} + 2x - 15}},\;\;{\rm{when \,\,}}x \ne - 5\\\,\,a\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,,{\rm{when\,\, }}x = - 5\end{array} \right.$   $x = - 5$ is continuous at $x = - 5$, then the value of $'a'$ will be
$\int\limits^1_0\frac{\text{x}}{(1-\text{x})^{54}}\text{ dx}=$
The velocity of a particle at time $t$ is given by the relation $v = 6t - {{{t^2}} \over 6}$. The distance traveled in $3$ seconds is, if $s = 0$ at $t = 0$