Question

Jika x - 1/x = 4, maka x^4 + 1/x^4 = ... lebih jelasnya lagi di foto

Answer 1

X - (1/x) = 4
=> (x - (1/x))^2 = 4^2
=> x^2 - 2 . x . 1/x + 1/x^2 = 16
=> x^2 - 2 + 1/x^2 = 16
=> x^2 + 1/x^2 = 18

(x^2 + 1/x^2)^2 = 18^2
=> x^4 + 2 . x^2 . 1/x^2 + 1/x^4 = 324
=> x^4 + 2 + 1/x^4 = 324
=> x^4 + 1/x^4 = 322