a: \(=4x^2-25-4x^2+12x-9-12x=-34\)

b: \(=8y^3-12y^2+6y-1-2y\left(4y^2-12y+9\right)-12y^2+12y\)

\(=8y^3-24y^2+18y-1-8y^3+24y^2-18y=-1\)

c: \(=x^3+27-x^3-20=7\)

d: \(=3y\left(9y^2+12y+4\right)-27y^3+1-36y^2-12y-1\)

\(=27y^3+36y^2+12y-27y^3-36y^2-12y\)

=0

Bài 2:

1: \(\left(2x-1\right)^2-4\left(2x-1\right)=0\)

=>\(\left(2x-1\right)\left(2x-1-4\right)=0\)

=>(2x-1)(2x-5)=0

=>\(\left[{}\begin{matrix}2x-1=0\\2x-5=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{2}\\x=\dfrac{5}{2}\end{matrix}\right.\)

2: \(9x^3-x=0\)

=>\(x\left(9x^2-1\right)=0\)

=>x(3x-1)(3x+1)=0

=>\(\left[{}\begin{matrix}x=0\\3x-1=0\\3x+1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=\dfrac{1}{3}\\x=-\dfrac{1}{3}\end{matrix}\right.\)

3: \(\left(3-2x\right)^2-2\left(2x-3\right)=0\)

=>\(\left(2x-3\right)^2-2\left(2x-3\right)=0\)

=>(2x-3)(2x-3-2)=0

=>(2x-3)(2x-5)=0

=>\(\left[{}\begin{matrix}2x-3=0\\2x-5=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{2}\\x=\dfrac{5}{2}\end{matrix}\right.\)

4: \(\left(2x-5\right)\left(x+5\right)-10x+25=0\)

=>\(2x^2+10x-5x-25-10x+25=0\)

=>\(2x^2-5x=0\)

=>\(x\left(2x-5\right)=0\)

=>\(\left[{}\begin{matrix}x=0\\2x-5=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=\dfrac{5}{2}\end{matrix}\right.\)

Bài 1:

1: \(3x^3y^2-6xy\)

\(=3xy\cdot x^2y-3xy\cdot2\)

\(=3xy\left(x^2y-2\right)\)

2: \(\left(x-2y\right)\left(x+3y\right)-2\left(x-2y\right)\)

\(=\left(x-2y\right)\cdot\left(x+3y\right)-2\cdot\left(x-2y\right)\)

\(=\left(x-2y\right)\left(x+3y-2\right)\)

3: \(\left(3x-1\right)\left(x-2y\right)-5x\left(2y-x\right)\)

\(=\left(3x-1\right)\left(x-2y\right)+5x\left(x-2y\right)\)

\(=(x-2y)(3x-1+5x)\)

\(=\left(x-2y\right)\left(8x-1\right)\)

4: \(x^2-y^2-6y-9\)

\(=x^2-\left(y^2+6y+9\right)\)

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

\(=\left(x-y-3\right)\left(x+y+3\right)\)

5: \(\left(3x-y\right)^2-4y^2\)

\(=\left(3x-y\right)^2-\left(2y\right)^2\)

\(=\left(3x-y-2y\right)\left(3x-y+2y\right)\)

\(=\left(3x-3y\right)\left(3x+y\right)\)

\(=3\left(x-y\right)\left(3x+y\right)\)

6: \(4x^2-9y^2-4x+1\)

\(=\left(4x^2-4x+1\right)-9y^2\)

\(=\left(2x-1\right)^2-\left(3y\right)^2\)

\(=\left(2x-1-3y\right)\left(2x-1+3y\right)\)

8: \(x^2y-xy^2-2x+2y\)

\(=xy\left(x-y\right)-2\left(x-y\right)\)

\(=\left(x-y\right)\left(xy-2\right)\)

9: \(x^2-y^2-2x+2y\)

\(=\left(x^2-y^2\right)-\left(2x-2y\right)\)

\(=\left(x-y\right)\left(x+y\right)-2\left(x-y\right)\)

\(=\left(x-y\right)\left(x+y-2\right)\)

a: \(=3y^2-5x^2y^3-2y^2+3x^2y^3=y^2-2x^2y^3\)

b: \(=6x-y+2x^2+3y^2-2x^2+x=7x-y+3y^2\)

c: \(=x-y+4y^2-6xy+\dfrac{10x^2}{y}\)

\(a.\left(9x^2y^3-15x^4y^4\right):3x^2y-\left(2-3x^2y\right)y^2\)

\(=3y^2-5x^2y^3-2y^2+3x^2y^3\)

\(=y^2-2x^2y^3\)

\(b.\left(6x^2-xy\right):x+\left(2x^3y+3xy^2\right):xy-\left(2x-1\right)x\)

\(=6x-y+2x^2+3y-2+x\)

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

\(c.\left(x^2-xy\right):x+\left(6x^2y^5-9x^3y^4+15x^4y^3\right):\dfrac{3}{2}x^2y^3\)

\(=x-y+4y^2-6xy+10x^2\)

Oa, giờ mới biết bác cũng ở box Toán :))

A= 3x² y-11x²-5y.8xy-5+6

=(3-11-5.8-5+6).(x².x².x).(y.y.y)

=-47x⁵y³

a: \(=\dfrac{27a^6b^3\cdot a^2b^6}{a^8b^8}=27b\)

b: \(=3y^2-5x^2y^3-2y^2+3x^2y^3\)

\(=y^2-2x^2y^3\)

c: \(=6x-y+2x^2+3y-2x^2+x\)

\(=7x+2y\)

d: \(=x-y+2y^2-6xy+\dfrac{10x^2}{y}\)

A=2(x+y)+3xy(x+y)+5x²y²(x+y)+2

A=2.0+3xy.0+5x²y².0+2

A=2

B=xy(x+y)+2x²y (x+y)+5

B=xy.0+2x²y.0+5=5

a,Ta có 2(x+y)+3xy(x+y)+5x²y²(x+y)+4

Xg thay x+y=0 vào là dc bn nhó

Chúc bn hok tốt

\(a,3x^3y^3-15x^2y^2=3x^2y^2\left(xy-5\right)\)

\(b,5x^3y^2-25x^2y^3+40xy^4\)

\(=5xy^2\left(x^2-5xy+8y^2\right)\)

\(c,-4x^3y^2+6x^2y^2-8x^4y^3\)

\(=-2x^2y^2\left(2x-3+4x^2y\right)\)

\(d,a^3x^2y-\frac{5}{2}a^3x^4+\frac{2}{3}a^4x^2y\)

\(=a^3x^2\left(y-\frac{5}{2}x^2+\frac{2}{3}ay\right)\)

\(e,a\left(x+1\right)-b\left(x+1\right)=\left(x+1\right)\left(a-b\right)\)

\(f,2x\left(x-5y\right)+8y\left(5y-x\right)\)

\(=2x\left(x-5y\right)-8y\left(x-5y\right)=\left(x-5y\right)\left(2x-8y\right)\)

\(g,a\left(x^2+1\right)+b\left(-1-x^2\right)-c\left(x^2+1\right)\)

\(=\left(x^2+1\right)\left(a-b-c\right)\)

\(h,9\left(x-y\right)^2-27\left(y-x\right)^3\)

\(=9\left(x-y\right)^2+27\left(x-y\right)^3\)

\(=9\left(x-y\right)^2\left(1+3x-3y\right)\)

$a,3x^3{y}^3-15x^2{y}^2=3x^2{y}^2\left(xy-5\right)$

$b,5x^3{y}^2-25x^2{y}^3+40x{y}^4$

$=5x{y}^2\left(x^2-5xy+8y^2\right)$

$c,-4x^3{y}^2+6x^2{y}^2-8x^4{y}^3$

$=-2x^2{y}^2\left(2x-3+4x^{2}y\right)$

$d,a^3{x}^{2}y-\frac{5}{2}{a}^3{x}^4+\frac{2}{3}{a}^4{x}^{2}y$

$=a^3{x}^2\left(y-\frac{5}{2}{x}^2+\frac{2}{3}ay\right)$

$e,a\left(x+1\right)-b\left(x+1\right)=\left(x+1\right)\left(a-b\right)$

$f,2x\left(x-5y\right)+8y\left(5y-x\right)$

$=2x\left(x-5y\right)-8y\left(x-5y\right)=\left(x-5y\right)\left(2x-8y\right)$

$g,a\left(x^2+1\right)+b\left(-1-x^2\right)-c\left(x^2+1\right)$

$=\left(x^2+1\right)\left(a-b-c\right)$

$h,9{\left(x-y\right)}^2-27{\left(y-x\right)}^3$

$=9{\left(x-y\right)}^2+27{\left(x-y\right)}^3$