1) 3x³ y²-6x.x.y³ + 9x²y²
2) 12x²y – 18xy² – 30y²
3) 5(x-y) – y(x-y)
4) y(x-z) +z(z-x)
5) 27x² (y-1) -9x²(1-y)
6) 36-12x+ x²
7) 4x² + 12x+9
9) 8x ³ + $\frac{1}{27}$
10) 25-4x ²-4xy-y ²
11) x ² + 2xy+y ²-xz-yz
1) 3x³ y²-6x.x.y³ + 9x²y²
2) 12x²y – 18xy² – 30y²
3) 5(x-y) – y(x-y)
4) y(x-z) +z(z-x)
5) 27x² (y-1) -9x²(1-y)
6) 36-12x+ x²
7) 4x² + 12x+9
9) 8x ³ + $\frac{1}{27}$
10) 25-4x ²-4xy-y ²
11) x ² + 2xy+y ²-xz-yz
`1, 3x³y² – 6x²y³ + 9x²y²`
`= 3x²y².(x – 2y + 3)`
`2, 12x²y – 18xy² – 30y²`
`= 6y(2x² – 3xy – 5y)`
`3, 5(x – y) – y(x – y)`
`= (x – y)(5 – y)`
`4, y(x – z) + z(z – x)`
`= (x – z)(y – z)`
`5, 27x²(y – 1) – 9x²(1 – y)`
`= 27x²(y – 1) + 9x²(y – 1)`
`= 36x²(y -1)`
`6, 36 – 12x + x²`
`= x² – 2.6x + 6²`
`= (x – 6)²`
`7, 4x² + 12x + 9`
`= (2x)² + 2.2.3x + 3²`
`= (2x + 3)²`
`9, 8x³ +1/27 `
`= (2x)³ + (1/3)³ `
`= (2x + 1/3)(4x² – 2x/3 + 1/9)`
`10, 25 – 4x² – 4xy – y²`
`= 25 – (4x² + 4xy + y²)`
`= (5 – 2x – y)(5 + 2x + y)`
`11, x² + 2xy + y² – xz – yz `
`= (x + y)(x + y – z)`
Học tốt !
Đáp án:
1, 3x³y² – 6x²y³ + 9x²y²
= 3x²y².(x – 2y + 3)
2, 12x²y – 18xy² – 30y²
= 6y(2x² – 3xy – 5y)
3, 5(x – y) – y(x – y)
= (x – y)(5 – y)
4, y(x – z) + z(z – x)
= y(x – z) – z(x – z)
= (x – z)(y – z)
5, 27x²(y – 1) – 9x²(1 – y)
= 27x²(y – 1) + 9x²(y – 1)
= (27x² + 9x²)(y – 1)
= 36x²(y -1)
6, 36 – 12x + x²
= x² – 2.6x + 6²
= (x – 6)²
7, 4x² + 12x + 9
= (2x)² + 2.2.3x + 3²
= (2x + 3)²
9, 8x³ + $\frac{1}{27}$
= (2x)³ + ($\frac{1}{3}$)³
= (2x + $\frac{1}{3}$)(4x² – $\frac{2x}{3}$ + $\frac{1}{9}$)
10, 25 – 4x² – 4xy – y²
= 25 – (4x² + 4xy + y²)
= 5² – (2x + y)²
= (5 – 2x – y)(5 + 2x + y)
11, x² + 2xy + y² – xz – yz
= (x + y)² – z(x + y)
= (x + y)(x + y – z)