Question

Use an identity to find the value of expression. sin 40° csc 40°​

Answer 1

Explanation:

1. sin37xcsc37

For this use the recipricol identity. csc37 = 1/sin37

sin37x(1/sin37) = (sin37)/(sin37) = 1

2. sec^2(23) - tan^2(23)

For this one use the pythagorean identity

sec^2(23) = 1+tan^2(23)

1+tan^2(23) - tan^2(23) = 1