IB Calculus Problem 15

Let \(f(x) = 3 Cos2x + Sin^2x\).

  1. Show that \(f^\prime(x) = -5Sin2x\).

  2. In the interval \(\frac{\pi}{4} \leq x \leq \frac{3\pi}{4}\), a normal to the graph of \(f\) has equation \(x = k\).

    Find the value of \(k\).

Published by Annie Bernatchez in «calculus». Key Words: IB, question