把下列格式分解因式,(1)x^4+64(2)x^3-11x^2+31x-21

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/09 04:37:00
把下列格式分解因式,(1)x^4+64(2)x^3-11x^2+31x-21

把下列格式分解因式,(1)x^4+64(2)x^3-11x^2+31x-21
把下列格式分解因式,
(1)x^4+64
(2)x^3-11x^2+31x-21

把下列格式分解因式,(1)x^4+64(2)x^3-11x^2+31x-21
x^4+64=X^4+64+16X^2-16X^2
=(X^2+8)-16X^2
=(X^2+8-4X)(X^2+8+4X)
x^3-11x^2+31x-2
=(x³-1)-(11x³-31x+20)
=(x-1)(x²+x+1)-(11x-20)(x-1)
=(x-1)(x²+x+1-11x+20)
=(x-1)(x²-10x+21)
=(x-1)(x-3)(x-7)