Question

qual resposta
x4 - 25x2 = 0

Answer 1

x^4 - 25x^2 = 0
x^2(x^2 - 25)  = 0

x^2 = 0 ==> x = 0
====================================================

x^2 - 25 = 0

x^2 = 25 ==> x = +/- V25 ==> x = +/- 5