" 8.If "alpha+beta=(pi)/(2)" ,show that the maximum value of "cos alpha cos beta" is "(1)/(2)

If alpha+beta=90^(0) ,show that the maximum value of cos alpha.cos beta is (1)/(2)

If alpha+beta=90^@ , show that the maximum value of cos alpha cos beta is (1)/(2)

If alpha + beta = 90^0 , show that the maximum value of cos alpha.cos beta is 1/2 .

If alpha+beta=pi/2 , then the maximum value of cosalpha cos beta is:

if alpha and beta satisfy sin alpha cos beta=-(1)/(2), then the greatest value of 2cos alpha sin beta is

If alpha and beta satisfy sin alpha cos beta=-((1)/(2)), then the greatest value of 2cos alpha sin beta is

Let alpha , beta be such that pi lt alpha - beta lt 3 pi . If sin alpha + sin beta =-(21)/(65) and cos alpha + cos beta =-(27)/(65) , then the value of cos""(alpha - beta )/(2) is

If alpha and beta satisfy sinalpha cos beta=-1/2 , then the greatest value of 2cos alpha sin beta is ……….

IF alpha+beta=pi/2 , then cos alpha cos beta has a maximum value at beta =