SOLUTION: If sin theta equals 2/5 and sec theta is less than 0, find cos theta and tan theta

Algebra ->  Trigonometry-basics -> SOLUTION: If sin theta equals 2/5 and sec theta is less than 0, find cos theta and tan theta      Log On


   

Question 824927: If sin theta equals 2/5 and sec theta is less than 0, find cos theta and tan theta
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
If sin theta equals 2/5 and sec theta is less than 0, find cos theta and tan theta
***
letx=theta
reference angle in quadrant II, in which cos and tan<0
cosx=-sqrt%281-sin%5E2%28x%29%29=-sqrt%281-4%2F25%29=-sqrt%2821%2F25%29=-sqrt%2821%29%2F5%29
tanx=sinx/cosx=2/-√21=-2√21/21