Question

If the cos 90° = 0, then the sin 0° = _____.

Answer 1

Cos 90 is indeed 0

Sin 0 is Also 0

Answer 2

0?

Answer 3

Sine and Cosine are cofunctions:\[\Large\bf\sf \cos(\text{angle})\quad=\quad \sin(90^o-\text{angle})\]

\[\Large\bf\sf \cos(90^o)\quad=\quad \sin(90^o-90^o)\]