tan theta=-3.966 and pie/2<theta<pie Find sin theta

Question

Find the values of sin theta and cos theta 

Answer 1

arctan(-3.966) = -75.848 degrees, but of course this in in quadrant IV.

 

correcting to quadrant II, angle is 104.152 degrees, approx.

 

now ask your calculator what are the sine and cosine of the above angle.