Question

Evaluate each of the following:

cos² 30° + cos² 45° + cos² 60°+ cos² 90°

Answer 1

cos² 30° + cos² 45° + cos² 60°+ cos² 90°

= \((\frac{\sqrt3}{2})^2\) + \((\frac{1}{\sqrt{2}})^2\) = \((\frac{1}{2})^2\) + (0)²

^{= \(\frac{3}4\) + \(\frac{1}2\) + \(\frac{1}4\) = \(\frac{3}2\)}