" If tan "A=n tan B" and "sin A=m sin B," prove that "cos^(2)A

If tan A = n tan B and sin A = m sin B , show that cos^(2)A= (m^(2)-1)/(n^(2)-1) .

If tanA=n tan B and sinA=m sin B, then the value of cos^2 A is यदि tanA=n tan B और sinA=m sin B, तो cos^2 A का मान है

If "tan" alpha= n tan beta and sin alpha =m sin beta prove that : cos^(2)alpha=(m^(2)-1)/(n^(2)-1)

If tan alpha= n tan beta and sin alpha= m sin beta , prove that cos^2 alpha= (m^2-1)/(n^2-1) .

If tan A + sin A = m and tan A - sin A = n, prove that : m^(2) - n^(2) = 4 sqrt (mn)

If the angles of a triangle be, A,B,C and cos theta (sin B+ sin C) = sin A , prove that "tan"^(2)( theta)/(2)="tan" (B)/(2) "tan"(C)/(2)

If a cos A+b sin A=m and a sin A-b cos A=n prove that a^(2)+b^(2)=m^(2)+n^(2)

If sin A=a cos B and cos A=b sin B then tan^(2)B =

If cos A+sin B=m and sin A+cos B=n , prove that 2sin(A+B)=m^2+n^2-2.

If tan A=1//2, tan B=1//3 , then prove that cos 2A=sin2B .