Đáp án:
`6)(x²-4x+1)(x²-6x+1)`
`8)(x-1)(x+2)(x²-11x-2)`
`10)3(x-1)(x+4)(x²-x-4)`
Giải thích các bước giải:
`6)x^4-10x³+26x²-10x+1`
`=x^4-4x³-6x³+x²+24x²+x²-6x-4x+1`
`=(x^4-4x³+x²)-(6x³-24x²+6x)+(x²-4x+1)`
`=x²(x²-4x+1)-6x(x²-4x+1)+(x²-4x+1)`
`=(x²-4x+1)(x²-6x+1)`
`8)x^4-10x³-15x²+20x+4`
`=x^4-11x³+x³-2x²-11x²-2x²-2x+22x+4`
`=(x^4-11x³-2x²)+(x³-11x²-2x)-(2x²-22x-4)`
`=x²(x²-11x-2)+x(x²-11x-2)-2(x²-11x-2)`
`=(x²+x-2)(x²-11x-2)`
`=(x²+2x-x-2)(x²-11x-2)`
`=[x(x+2)-(x+2)](x²-11x-2)`
`=(x-1)(x+2)(x²-11x-2)`
`10)3x^4+6x³-33x²-24x+48`
`=3(x^4+2x³-11x²-8x+16)`
`=3(x^4-x³+3x³-4x²-3x²-4x²-12x+4x+16)`
`=3[(x^4-x³-4x²)+(3x³-3x²-12x)-(4x²-4x-16)]`
`=3[x²(x²-x-4)+3x(x²-x-4)-4(x²-x-4)]`
`=3(x²+3x-4)(x²-x-4)`
`=3(x²+4x-x-4)(x²-x-4)`
`=3[x(x+4)-(x+4)](x²-x-4)`
`=3(x-1)(x+4)(x²-x-4)`
