If `tan^2alpha=1+2tan^2beta`, prove that, `cos 2 beta=1+2 cos 2 alpha`.

If tan^2alpha = 1 + tan^2beta ,then prove that cos^2 beta = cot^2alpha

If tan^(2) alpha = 1 + 2 tan^(2) beta, "prove that ," cos 2 beta = 1 + 2 cos 2 alpha

If tan^2 alpha = 1 + 2 tan^2 beta , show that cos2 beta = 1 + 2cos 2alpha .

If a tan alpha+b tan beta=(a+b) tan ((alpha+beta)/2) , where alpha ne beta , prove that : a cos beta= b cos alpha .

If a tan alpha+b tan beta=(a+b)tan((alpha+beta)/(2)) where alpha!=beta ,prove that a cos beta=b cos alpha

If 2 tan (alpha/2)=tan (beta/2), prove that cos alpha=(3+5 cos beta)/(5+3 cos beta).

If 2tan alpha=3tan beta, prove that tan(alpha-beta)=(sin2 beta)/(5-cos2 beta)

If 2tan alpha=3tan beta, prove that tan(alpha-beta)=(sin2 beta)/(5-cos2 beta)

If cos^2alpha-sin^2alpha=tan^2beta," then prove that "tan^2alpha=cos^2beta-sin^2beta .

If cos^2alpha-sin^2alpha=tan^2beta," then prove that "tan^2alpha=cos^2beta-sin^2beta .