# For what value of theta is the fraction 1/tan of theta undefined?Please explain this, I am so so confused.

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Let `y= 1/tantheta `

We need to find the values of `theta` such that the function (y) is defined.

Since `tan(theta)` is in the denominator, then we know that `tan(theta)` can not be 0.

==> `tantheta != 0`

Now we will find the values where `tan(theta)= 0` and exclude them from the domain.

`==gt tan(theta)= 0 `

`==gt (sintheta)/(costheta)= 0 `

`==gt sin(theta)= 0 `

`==gt theta = 2npi` (n= 0, 1, 2, ...)

==> Then `1/(tantheta)` is not defined when `theta= 2npi` (n= 0, 1, 2..)