Question

if x+1/x = 5 , find x*4 + 1/x*4​

Answer 1

x+1/x = 5

(x+1/x)² = x²+1/x²+2

(5)² = x²+1/x²+2

25-2 = x²+1/x² => 23

(x²+1/x²)² = x⁴+1/x⁴+2

(23)² = x⁴+1/x⁴+2

529-2 = x⁴+1/x⁴

527 = x⁴+1/x⁴