Mathematics

Problem

For the curve given by

x=a\cos t+b\sin t

and

y=a\sin t-b\cos t\;(a\neq 0,\,b\neq 0)

, the value of

\dfrac{d^{2}y}{dx^{2}}

t=0

is a)

\dfrac{a^{2}+b^{2}}{a^{3}}

\dfrac{a^{2}+b^{2}}{b^{3}}

\dfrac{a^{2}-b^{2}}{b^{3}}

\dfrac{a^{2}+b^{2}}{b^{4}}