# Answer to Question #13075 in Trigonometry for Avruti Patel

Question #13075

If cos(alpha)+cos(beta)=0=sin(alpha)+sin(beta) then find the value of cos2(alpha)+cos2(beta)

Expert's answer

since cos(alpha)+cos(beta)=0=sin(alpha)+sin(beta), then this angles represent

opposite points on the unit circle.

Thus alpha=beta+pi

So,

cos2(alpha)+cos2(beta)=2cos(2*beta), where angles are determined by

alpha=beta+pi.

opposite points on the unit circle.

Thus alpha=beta+pi

So,

cos2(alpha)+cos2(beta)=2cos(2*beta), where angles are determined by

alpha=beta+pi.

## Comments

Assignment Expert07.08.13, 17:19pi=3,1415926.. is a mathematical constant that is the ratio of a circle's circumference to its diameter.

Brenda05.08.13, 23:41what is pi ?

## Leave a comment