7.2cos theta=x+(1)/(x)=60-cosin180,2cos3 theta-x^(3)+(1)/(x)1

If 2costheta=x+(1)/(x) then prove that, 2cos3theta=x^(3)+(1)/(x^(3)) .

If x+(1)/(x)=2cos theta then x^(3)+(1)/(x^(3)) is

If 2 cos theta = x + (1)/(x), prove that 2 cos 3 theta = x ^(3) + (1)/(x ^(3)).

If 2costheta=x+(1/x) prove that 2cos3theta=x^3+(1/x^3)

If x+(1)/x=2 cos theta , " then " x^(3)+(1)/(x^(3))=

If x+(1)/(x)=2cos theta, then x^(3)+(1)/(x^(3)) is equal to

2cos theta=x+(1)/(x) and 2cos phi=y+(1)/(y) then (A)x^(n)+(1)/(x^(n))=2cos(n theta)n in Z(B)(x)/(y)+(y)/(x)=2cos(theta-phi)(C)xy+(1)/(Xy)=2cos(theta+phi)(D)x^(m)y^(n)+(1)/(x^(m)y^(n))=2(cos m theta+n phi),m,n in Z

If 2 cos theta=x+(1)/(x) , find the value of 2cos 3 theta

IF 2 costheta=x+1/x then show that 2 cos3 theta=x^3+1/x^3