prove (tan^3x/1 tan^2x) (cot^3x/1 cot^2) = (1-2sin^2x cos^2x)/sinx cosx

Answer 1

I assume the missing operators are +, and thus that you mean

tan^3x/(1+tan^2x) * cot^3x/(1+cot^2x)
= (1-2sin^2x cos^2x)/(sinx cosx)

but that is in fact not true. Maybe you can fix it up and try again.