Question

X^4-3x^2+2=0
Đặt ẩn t

Answer 1

`x_(1) = - √(2) \: .\: x_(2) = - 1 \: . \: x_(3) = 1 \: . \: x_(4) = √(2)`

Explanation:

x⁴ - 3x² + 2 = 0

x^2×2 - 3x² + 2 = 0

(x²)² - 3x² + 2 = 0

t² - 3t + 2 = 0

t = 1, t = 2

x² = 1, x² = 2

x = -1, x = 1

x = - square root 2, x = square root 2

`x_(1) = - √(2) \: .\: x_(2) = - 1 \: . \: x_(3) = 1 \: . \: x_(4) = √(2)`