Question

Evaluate:
cos45⁰ cos30⁰ + sin45⁰ sin30⁰

Answer 1

On substituting the values of various T-ratios, we get:
cos45⁰ cos30⁰ + sin45⁰ sin30⁰

^{`=(1/sqrt(2) xxsqrt(3)/2 +1/sqrt(2) xx1/2) = (sqrt(3)/(2sqrt(2)) + 1/(2sqrt(2)) )= ((sqrt(3)+1)/(2sqrt(2)))`}