Derivative Rules of Constant, Sum, Difference Practice Test

If $$y = 2\sin(t) + 3\cos(t)$$, find the value of $$\frac{d^2y}{dt^2}$$ at $$t = \frac{\pi}{2}$$.

What is the derivative of $$y = 5x - \frac{\cos(x)}{2} + e$$?