Question

if 2x +1/x=5,let's find the value of 4x²+1/x²​

Answer 1

Answer:

From the equation we see that RHS it is a square of (x+1/2x).

Let x+(1/2x)=y

So the given equation can be written as,

f(2y)=y^2

Let 2y=z, so, y^2 = (z^2)÷(4)

Therefore replace 2y by z

f(z) = (z^2)÷4.

Change the variable to x we get,

f(x) = (x^2)÷4.