" If "cos alpha=(2sqrt(2))/(3),sin beta=(4)/(5)," then "find cos(alpha+beta)

if cos alpha=(3)/(5) and cos beta=(4)/(5) find the value of cos((alpha-beta)/(2))

If cos alpha = (3)/(5) , cos beta = (4)/(5) , find the value of cos ""(( alpha - beta)/( 2)), assuming alpha and beta to be acute angles.

If sin alpha=(3)/(5) and cos beta=(9)/(41) find the value of sin(alpha-beta) and cos(alpha+beta)

If cos (alpha+beta)=(4)/(5), sin (alpha-beta)=(5)/(13) and 0 lt alpha, beta lt (pi)/(2) then cos 2 alpha=

if cos alpha=(11)/(61) and sin beta=(4)/(5), find the values of sin^(2)((alpha-beta)/(2)) and cos^(2)((alpha+beta)/(2))

If 0

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

If cos alpha+cos beta=(1)/(3) and sin alpha+sin beta=(1)/(4) prove that cos[(alpha-beta)/(2)]=+-((5)/(24))

If sin 2 alpha + sin 2 beta = 3 "and" cos 2 alpha + cos 2 beta = 4,"then"- cos2 (alpha + beta)=

Ifsin^(4)alpha+cos^(4)beta+2=4sin alpha cos beta,0<=alpha,beta<=(pi)/(2) then find the value of (sin alpha+cos beta)