Question

Which of the following are examples of multiplicative inverses?

1) csc x and sin x
2) tan x and cot x
3) cos^-1 and cos x
4) ln x and e^x

A. All of these
B. 1 and 2
C. 1,2, and 3
D. 3 and 4

I know it's not all of them...but I'm leaning toward B. Help please?

Thank you!

Answer 1

B is indeed correct. If two functions are multiplicative inverses then that means that the product of the two functions equals 1.

Note that cos^(-1) denotes the functional inverse of cos, so this not the same as 1/cos(x).