分解因式 x^4-3x²y²+2y^4

问题描述:

分解因式 x^4-3x²y²+2y^4

原式=(x²-y²)(x²-2y²)=(x+y)(x-y)(x+√2y)(x-√2y)

x^4-3x²y²+2y^4
用十字相乘法:
x^2 -y^2
\ /
/\
x^2 / \ -2y^2
得:
x⁴-3x²y²+2y⁴=(x²-y²)(x²-2y²)=(x+y)(x-y)(x+√2y)(x-√2y)

x^4-3x²y²+2y^4
=(x²-2y²)(x²-y²)
=(x-√2y)(x+√2y)(x-y)(x+y)