x^4-3x2+1 =x^4-2X²+1-X²
=（X²-1)²-X²
=(X²+X-1)(X²-X-1)
x^4+2x2+9 =
=x^4+6X²+9-4X²
=(X²+3)²-(2x)²
=(X²+2X+3)(X²-2X+3)
x四次方-3x2+1 =x四次方-2X²+1-X²
=（X²-1)²-X²
=(X²+X-1)(X²-X-1)
x四次方+2x2+9 =
=x四次方+6X²+9-4X²
=(X²+3)²-(2x)²
=(X²+2X+3)(X²-2X+3)
内容全部来源于网络收集，如有侵权，请联系网站删除：QQ：24596024