Question

Evaluate each of the following:

sin 45° sin 30° + cos 45° cos30°

Answer 1

Given: sin 45° sin30° + cos 45°cos 30°

To find: The value of above equation. 

Solution: Use the values:

sin 30 = \(\frac{1}2\), cos 30 = \(\frac{\sqrt3}2\)

solve, sin 45sin30 + cos45cos30 = \((\frac{1}{\sqrt2}\times\frac{1}2)\) + \((\frac{1}{\sqrt2}\times\frac{\sqrt3}2)\)