`n)x^2+4x+3`
`=x^2+3x+x+3`
`=x(x+3)+(x+3)`
`=(x+3)(x+1)`
`b)x^2+6x+8`
`=x^2+4x+2x+8`
`=x(x+4)+2(x+4)`
`=(x+4)(x+2)`
`->` tách ra nha bạn
\(10,\\ a,x^2-6x+5\\ =x^2-x-5x+5\\ =x\left(x-1\right)-5\left(x-1\right)\\ =\left(x-1\right)\left(x-5\right)\)
\(b,x^2+6x+8\\ =x^2+4x+2x+8\\ =x\left(x+4\right)+2\left(x+4\right)\\ =\left(x+4\right)\left(x+2\right)\)
\(c,2x^2+10x+8\\ =2\left(x^2+5x+4\right)\)
\(d,x^2-5x+14\)
`->` Có đúng đề không cậu nhỉ ?
\(e,x^2-7x+10\\ =x^2-2x-5x+10\\ =x\left(x-2\right)-5\left(x-2\right)\\ =\left(x-2\right)\left(x-5\right)\)
\(g,3x^2-5x-2\\ =3x^2+x-6x-2\\ =x\left(3x+1\right)-2\left(3x+1\right)\\ =\left(3x+1\right)\left(x-2\right)\)
\(h,2x^2+x-6\\ =2x^2+4x-3x-6\\ =2x\left(x+2\right)-3\left(x+2\right)\\ =\left(x+2\right)\left(2x-3\right)\)
\(i,x^2-9x+18\\ =x^2-3x-6x+18\\ =x\left(x-3\right)-6\left(x-3\right)\\ =\left(x-3\right)\left(x-6\right)\)
\(k,2x^2-6x+9\)
`->` Cậu xem lại đề
\(e,3x^2-5x-2\\=3x^2+x-6x-2\\ =x\left(3x+1\right)-2\left(3x+1\right)\\ =\left(3x+1\right)\left(x-2\right)\)
`m,` \(x^2-5+6\)
`->` Cậu xem lại đề
