Question

Cos 20° cos 40° - sin 5° sin 25°=

Answer 1

Values are:

Cos 20° = 0.989

Cos 40° = 0.76604

Sin 5° = 0.08716

Sin 25° = 0.42262

Cos 20° x Cos 40° - Sin 5° x sin 25°

0.989 x 0.76604 - 0.08716 x 0.42262

0.75761356 - 0.0368355592

= 0.7207780008

Here's your answer

Thanks!