Question

The expression 4 - cos² A is equivalent to

1)5 - sec² A
2)5 - sin² A
3)5 + sin² A
4)5/sec² A

Answer 1

4 - (1-sin^2 A)
so suspect another typo

4 + cos^2 A
4 + (1-sin^2 A)
5 - sin^2 A