Đáp án + giải thích các bước giải
1)(2x3-21x2+67x-60):(x-5)
=(2x3-10x2-11x+55x+12x-60):(x-5)
=[2x2(x-5)-11x(x-5)+12(x-5)]:(x-5)
=2x2-11x+12
2)(x4+2x3+x-25):(x2+5)
=(x4+5x2+2x3+10x-5x2-25-9x):(x2+5)
=[x2(x2+5)+2x(x2+5)-5(x2+5)-9x]:(x2+5)
=[(x2+5)(x2+2x-5)-9x]:(x2+5)
⇒(x4+2x3+x-25):(x2+5)=x2+2x-5 (dư -9x )
3)(27x3-8):(6x+9x2+4)
=((3x)3-23):(6x+9x2+4)
=(3x-2)(9x2+6x+4):(6x+9x2+4)
=3x-2