# Math Help - trigonometric function values

1. ## trigonometric function values

find sin (theta).

tan(theta)= - (sqrt)7/2

sec(theta)>0

I'm sorry if this is confusing to you all(math editor) I am also very confused! Please help!

2. You can solve for theta by taking the $arctan(-\frac{\sqrt(7)}{2})$. Then just plug in theta as the parameter for sin().

3. Originally Posted by momuvfour
find sin (theta).

tan(theta)= - (sqrt)7/2

sec(theta)>0

I'm sorry if this is confusing to you all(math editor) I am also very confused! Please help!
Dear momuvfour,

It is given that $sec\theta>0\Rightarrow{cos\theta<0}$That is theta is in the second or third quadrants. Hence we have to find values for $tan\theta=-\frac{\sqrt{7}}{2}$ such that theta will be in the second or third quadrants. Can you continue from here??

Dear macosxnerd101,

By taking $\theta=arctan\left(-\frac{\sqrt{7}}{2}\right)$ you have only considered the case where theta is in the second quadrant.