Question

How do you find the quadrants in which the terminal side of `theta` must lie given `sintheta` is positive and `cos theta` is negative?

Answer 1

`theta` is in `Q2`.

Explanation:

`sintheta` is postive in `Q1` and `Q2`, it is negative in `Q3` and `Q4` - so is `csctheta` as it is its reciprocal.

`costheta` is positive in `Q1` and `Q4`, it is negative in `Q2` and `Q3` - so is its reciprocal `sectheta`.

`tantheta` is positive in `Q1` and `Q3` and it is negative in `Q2` and `Q4` - so is `cottheta` as it is its reciprocal.

As `sintheta` is positive and `costheta` is negative,

`theta` is in `Q2`.