find the exact value of the expression:

6tan^2(π/4)+18sec^2(π/4).

2 answers

well, you should of course know that
tan(π/4) = 1
sec(π/4) = √2
and now you just plug and chug.
π/4 radians = 45°
you should know that tan45° = 1 and cos45° = 1/√2
so cos^2 45° = 1/2, which would make sec^2 45° = 2

take over