You need an eagle eye for this
Calculus
Level
3
\[\large y = 1 - \frac{(2x)^2}{2!} + \frac{(2x)^4}{4!} - \frac{(2x)^6}{6!} + \ldots\]
Find \(\dfrac{d^2y}{dx^2}\) at \(x = \pi\).
by
Akhil Bansal