Question

How do you evaluate `sec(-pi/18) * cos(37pi/18)`?

Answer 1

= 1

Explanation:

`sec (- pi/18) = 1/(cos (-pi/18)) = 1/cos (pi/18)`
`cos ((37pi)/18) = cos (pi/18 + (36pi)/18) = cos (pi/18)`
The product transform itself to:
`P = cos (pi/18)/(cos (pi/18)) = 1`