Question

If the sin 90° is 1, then the cos ____ °= _____.

90° ; 1 over 2

0° ; square root 2 over 2

90° ; square root 3 over 2

0° ; 1

Answer 1

Rule of trigonometric functions:-
sin a = cos(90 - a)
Here a = 90°.
sin 90 = cos (90 - 90)
1 = cos 0.
cos 0 = 1.

Answer 2

Do you understand it now?

Answer 3

No

Answer 4

Okay well let me explain it to you.

Answer 5

So is cos 0° = 1, because the angles are complementary