Câu hỏi của lê sỹ phát

Question

a) $x^2-9x+18$

b) $x^2-6x+8$

c) $x^2-5x-14$

✿✿❑ĐạT̐®ŋɢย❐✿✿ · Accepted Answer

a) $x^2-9x+18=x^2-3x-6x+18=x.\left(x-3\right)-6.\left(x-3\right)=\left(x-6\right).\left(x-3\right)$

b) $x^2-6x+8=x^2-2x-4x+8=x.\left(x-2\right)-4.\left(x-2\right)=\left(x-4\right).\left(x-2\right)$

c) $x^2-5x-14=x^2+2x-7x-14=x.\left(x+2\right)-7.\left(x+2\right)=\left(x-7\right).\left(x+2\right)$

Chúc bạn học tốt !Câu trả lời: a) $x^2-9x+18=x^2-3x-6x+18=x.\left(x-3\right)-6.\left(x-3\right)=\left(x-6\right).\left(x-3\right)$

b) $x^2-6x+8=x^2-2x-4x+8=x.\left(x-2\right)-4.\left(x-2\right)=\left(x-4\right).\left(x-2\right)$

c) $x^2-5x-14=x^2+2x-7x-14=x.\left(x+2\right)-7.\left(x+2\right)=\left(x-7\right).\left(x+2\right)$

Chúc bạn học tốt !

Trương Trường Giang · Answer

a) x2 − 9x + 18

= x2 - 6x - 3x + 18

= x(x - 6) - 3(x - 6)

= (x - 6)(x - 3)

b) x2 − 6x + 8

= x2 - 4x - 2x + 8

= x(x - 4) - 2(x - 4)

= (x - 4)(x - 2)

c) x2 − 5x − 14

= x2 − 7x + 2x − 14

= x(x - 7) + 2(x - 7)

= (x - 7)(x + 2)

Chúc bạn học tốt!!!Câu trả lời: a) x2 − 9x + 18