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

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.

Let alpha,beta be such that pi<(alpha-beta)<3pi . If sinalpha+sinbeta=-21/65 and cosalpha+cosbeta=-27/65 , then the value of cos((alpha-beta)/2) is

Let alphaandbeta be such that piltalpha-betalt3pi . If sinalpha+sinbeta=-(21)/(65)and cosalpha+cosbeta=-(27)/(65) , then the value of "cos"((alpha-beta))/(2) is

Let alpha, beta be such that pi lt=alpha lt=beta lt=3pi if sinalpha + sinbeta = -21/65 and cosalpha + cosbeta = -27/65 , then the value of cos""(alpha - beta)/65 is :

If cosalpha=3/5 and cosbeta=5/13 then cos^2((alpha+beta)/2)=16/65

If cosalpha+cosbeta=2/3 and sinalpha+sinbeta=2/5 then find the vvalue of tan((alpha+beta)/2)

If sinalpha+cosbeta=5/4 and cosalpha+sinbeta=3/4 , then value of sin(alpha+beta)=?

If sinalpha-sinbeta=a and cosalpha+cosbeta=b then write the value of "cos"(alpha+beta) .

If sinalpha=(1)/(3) and cosbeta=(4)/(5), " then find " sin(alpha+beta) .