Question

(sec^2x-1)(csc^2x-1)=1 prove the following identity

ive been stuck on this for hours please help

Answer 1

sec^2(x)-1 = tan^2(x)
csc^2(x)-1 = cot^2(x)

since cot = 1/tan, it follows immediately

Answer 2

A math tutor told me to FOIL it. This is just a hint, or starting point because I don't know for sure.