Question

How do you evaluate `tan(tan^-1(135))`?

Answer 1

135

Explanation:

`tan^-1` 135 means the angle whose tan is 135.

If we think about an angle whose tan we know:
Draw a right angled isosceles triangle.
The tan of a 45 degree angle is 1
So `tan^-1`(1) =45

Tan(45)=1
So instead of 45 I can write `tan^-1(1)`

Tan( `tan^-1(1)`)= 1

Likewise tan(`tan^-1(135)`)=135