If `tan A=1//2,tanB=1//3`, then prove that cos 2A = sin 2B.

If tanA=18/17 and tanB=1/35 prove that tan(A-B)=1

If tan(A+B)=3tanA , prove that sin(2A+B)=2sinB

If tanA=1/3 and tanB=1/7 , show that 2A+B=45^@

Prove that cos^-1x=2sin^-1sqrt((1-x)/2)

Prove that 1-8sin^2Acos^2A=cos4A

If tanA=a/(a+1) and tanB=1/(2a+1) .prove that A+B=45^@ ; ane(-1/2) and a ne -1

If cos^(2)alpha-sin^(2)alpha=tan^(2)beta , then prove thta tan^(2)alpha=cos^(2)beta-sin^(2)beta .

If sin A + cos 2A = 1/2 and cos A +sin 2A =1/3 , then find the value of sin 3A .

If (cos^4 alpha)/(cos^2beta)+(sin^4alpha)/(sin^2beta)=1 ,then prove that (cos^4beta)/(cos^2alpha)+(sin^4beta)/(sin^2alpha)=1