# Math

posted by
**Anonymous**
.

Which of the following are inverse functions?

1. Arcsin x and sin x

2. cos^-1 x and cos x

3. csc x and sin x

4. e^x and ln x

5. x^2 and +/- sqrt x

6. x^3 and cubic root of x

7. cot x and tan x

8. sin x and cos x

9. log x/3 and 3^x

I believe the answers are 2, 4, 6, and 9, but how come not the rest, especially csc/sin and cot/tan?

Thank you very much!