Question

Phân tích đa thức thành nhân tử:

1. x bình - 5x - 6

2. 11x bình + 5x - 6

3. 1 + 3x + 2x bình

4. 6 - 2x - 8x bình

5. 7 - 4x - 3x bình

Các bác giúp e vs, hứa sẽ tick, e cảm ơn nhiều !!!!!!!!!!!!!!!!

Answer 1

Phân tích đa thức thành nhân tử:

1. x² - 5x - 6

\(=x^2-6x+x-6\)

\(=\left(x^2-6x\right)+\left(x-6\right)\)

\(=x\left(x-6\right)+\left(x-6\right)\)

\(=\left(x+1\right)\left(x-6\right)\)

3. 1 + 3x + 2x²

\(=1+2x+x+2x^2\)

\(=\left(1+2x\right)+\left(x+2x^2\right)\)

\(=\left(1+2x\right)+x\left(1+2x\right)\)

\(=\left(1+2x\right)+\left(x+1\right)\)

4. 6 - 2x - 8x²

\(=6-8x+6x-8x^2\)

\(=\left(6+6x\right)-\left(8x+8x^2\right)\)

\(=6\left(1+x\right)-8x\left(1+x\right)\)

\(=\left(6-8x\right)\left(1+x\right)\)

5. 7 - 4x - 3x²

\(=7-7x+3x-3x^2\)

\(=\left(7-7x\right)+\left(3x-3x^2\right)\)

\(=7\left(1-x\right)+3x\left(1-x\right)\)

\(=\left(7+3x\right)\left(1-x\right)\)

Answer 2

1) \(x^2-5x-6\\ =x^2+x-6x-6\\ =x\left(x+1\right)-6\left(x+1\right)\\ =\left(x-6\right)\left(x+1\right)\)

3) \(1+3x+2x^2\\ =2x^2+2x+x+1\\ =2x\left(x+1\right)+\left(x+1\right)\\ =\left(x+1\right)\left(2x+1\right)\)