If `x` is any real number then show that `cos theta` cannot be equal to `x+ 1/x.`

If x be real show that costheta cannot be equal to x+1/x.

If x be real, show that cos theta cannot be equal to x+(1)/(x) .

If x is any non-zero real number,show that cos theta and sin theta can never equal to x+(1)/(x)

If x is any non-zero real number, show that costheta' a n d ' sintheta can never equal to x+1/x ,

For any real number of x and y, if cos x=cos y then:

If theta is any real number, then, in a triangle ABC, prove that a cos (B - theta) + b cos (A + theta) = c cos theta .

If x and y are real numbers such that sin^2theta=(x^2+y^2)/(2xy) show that x=y .

If x=(2sin theta)/(1+cos theta+sin theta), then prove that (1-cos theta+sin theta)/(1+sin theta) is equal to x

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

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