List of top Mathematics Questions on Second Order Derivatives asked in CBSE Class XII

If \( y = P \cos ux + Q \sin ux \), show that \( \frac{d^2y}{dx^2} + u^2y = 0 \).
If \(y = P \cos ux + Q \sin ux\), show that \(\frac{d^2y}{dx^2} + u^2y = 0\).