" 43.If "sin alpha=(4)/(5)" and "cos beta=(5)/(13)," prove that "cos(alpha-beta)/(2)=(8)/(sqrt(65))

If cos alpha=(4)/(5) and cos beta=(5)/(13), prove that (cos(alpha-beta))/(2)=(8)/(sqrt(65))

If cos alpha=4/5 and cos beta =5/13, prove that cos (alpha-beta)/2=28/65.

If cos alpha=(3)/(5) and cos beta=(5)/(13), then cos^(2)backslash(alpha-beta)/(2)=

If cos alpha = (3)/(5) , cos beta =(5)/(13) , "then " cos^(2) ((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 coa alpha+cos beta=(1)/(3) and sin alpha+sin beta prove that cos((alpha-beta)/(2))=+-(5)/(24)

If cos alpha=(12)/(13) and sin beta=(4)/(5) , then find sin(alpha+beta) .

pi

Le alpha and beta be such that pi

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