If α , β , γ are the angles made by a line with +ve directions of x ,y and z axes then the value of cos 2 α + cos ( β + γ ) cos ( β − γ ) is

If sin (x+y)=cos (x-y), then the value of cos^2x is :

If alpha, beta and gamma are angles made by the line with positive direction direction of X-axis, Y-axis and Z-axis respectively, then find the value of cos2alpha+cos2beta+cos2gamma .

If the angle made by a line with the positive directions of X and Y-axes are complementary angles then the angle made by the line with Z -axis is

Which of the following angles made by a line with co-ordinate axes are not possible?

If theta is an angle given by cos theta = (cos ^(2) alpha + cos ^(2) beta + cos ^(2) gamma)/( sin ^(2) alpha + sin ^(2) beta + sin ^(2) gamma) where alpha, beta, gamma are the equal angles made by line with the positive directions of the axes, then the measure of theta is

If sin x+sin y+sin z=3. Find the value of cos x+cos y+cos z

Let alpha, beta, gamma be the angles made by a line with the positive directions of the axes of reference in three dimensions. If theta is the acute angle given by costheta=(cos^(2)alpha+cos^(2)beta+cos^(2)gamma)/(sin^(2)alpha+sin^(2)beta+sin^(2)gamma) , then theta equal.