`I f5tanalphatanbeta=3(cos(alpha+beta)/(cos(alpha-beta)`

If cotalphacotbeta=3 ,show that (cos(alpha-beta))/(cos(alpha+beta))=2

If 5tan alpha tan beta=3 , then find the value of (cos(alpha+beta))/(cos(alpha-beta))

underset is f(alpha. beta)=cos^(2)+beta cos^(2)(alpha+beta)-2cos alpha cos beta cos(alpha+beta)

f(alpha,beta) = cos^2(alpha)+ cos^2(alpha+beta)- 2 cosalpha cosbeta cos(alpha+beta) is

If 0

Prove that: cos ^ (2) alpha + cos ^ (2) (alpha + beta) -2cos alpha cos beta cos (alpha + beta) = sin ^ (2) beta

If A = cos ^(2) alpha + cos ^2(alpha + beta)- 2 cos alpha cos beta cos (alpha + beta), then

Let f(alpha, beta) =|(cos (alpha + beta), -sin (alpha + beta), cos 2beta),(sin alpha, cos alpha, sin beta),(-cos alpha, sin alpha, cos beta)| The value of l=int_(0)^(pi//2)e^(beta)(f(0,0)+f((pi)/(2),beta)+f((3pi)/(2),(pi)/(2)-beta))dbeta is

The expression cos^2(alpha+beta)+cos^2(alpha-beta)-cos2alpha.cos2beta, is