Question

What does tan pi/2 equal?

Answer 1

`tan(pi/2)` is not defined.

Explanation:

You can find it out whwn you try to calculate it using identity

`tanx=sinx/cosx`

For `x=pi/2` the denominator of this expression is zero, so it cannot be calculated.

Answer 2

`tan(pi/2)` is undefined

Explanation:

In general the `tan` of an angle based on the unit circle in standard position is defined to be `y/x` where `(x,y)` is the coordinate of the terminal point of the radial arm.

...but at `pi/2`
`color(white)("XXX")x=0`
and division by `0` is undefined.