" Factors of "cos4 theta-cos4 phi" are "

A factor of cos 4theta - cos 4phi is

4cos6 theta cos4 theta cos2 theta=

The value of ((sin theta + sin phi)/(cos theta + cos phi)+ (cos theta - cos phi)/(sin theta - sin phi)) is :

If the sides of a triangle are in A.P. and the greater and the least angles are theta and phi respectively, then show that, 4(1-cos theta)(1-cos phi) = cos theta +cos phi

Let Delta = det [[without theta cos phi, without theta without phi, cos thetacos theta cos phi, cos theta without phi, -without theta-without theta without phi, without theta cos phi, 0]]

If cos theta =(4)/(5) " and cos " phi =(12)/(13) " where " theta " and " phi both lie in the fourth quadrant find the values of (i) " cos " (theta + phi) " " (ii) " sin " (theta -phi) " ' (iii) " tan " (theta + phi)

If sin theta+ sin phi = a, cos theta + cos phi = b, find the value of sin ( theta+phi) and cos 2theta + cos 2phi where |b|>|a|

If " "a cos phi = b cos theta," show that " a tan theta + b tan phi = (a+b) tan ((theta + phi)/2)