Question

if x^4+1/x^4=47 find the value of x^2+1/x^2

Answer 1

Step-by-step explanation:

add 2 on both sides

2 = 2* x²× 1/x²

(x²)² +(1/x²)²+ 2*x²*1/x² = 47+2 = 49

(x²+ 1/x²)² = 7²

x²+1/x² = +/- 7