Question

Oblicz równanie :

x² - 1/x² = 0

Answer 1

X²-1/x²=0

x²≠0 /*√
x≠0

x²-1=0
(x-1)(x+1)=0
x-1=0
x=1
x+1=0
x=-1

Answer 2

Zał. x^2 =/= 0 => x =/= 0
x^2 - 1/x^2 = 0 | * x^2 =/= 0
x^4 - 1 = 0
(x - 1)(x + 1)(x^2 + 1) = 0
( x = 1 lub x = -1 ) i x =/= 0
x należy do {-1; 1}