Thế mày làm đi

cho ít thôi thì làm

1: \(=6x^2+2x-15x-5-x^2+6x-9+4x^2+20x+25-27x^3-27x^2-9x-1\)

=-27x^3-18x^2+4x+10

2: =4x^2-1-6x^2-9x+4x+6-x^3+3x^2-3x+1+8x^3+36x^2+54x+27

=7x^3+37x^2+46x+33

5:

\(=25x^2-1-x^3-27-4x^2-16x-16-9x^2+24x-16+\left(2x-5\right)^3\)

\(=8x^3-60x^2+150-125+12x^2-x^3+8x-60\)

=7x^3-48x^2+8x-35

lên google

1) `2x(3x-1)-(2x+1)(x-3)`

`=6x^2-2x-2x^2+6x-x+3`

`=4x^2+3x+3`

2) `3(x^2-3x)-(4x+2)(x-1)`

`=3x^2-9x-4x^2+4x-2x+2`

`=-x^2-7x+2`

3) `3x(x-5)-(x-2)^2-(2x+3)(2x-3)`

`=3x^2-15x-(x^2-4x+4)-(4x^2-9)`

`=3x^2-15x-x^2+4x-4-4x^2+9`

`=-2x^2-11x+5`

4) `(2x-3)^2+(2x-1)(x+4)`

`=4x^2-12x+9+2x^2+8x-x-4`

`=6x^2-5x+5`

1: \(x\left(3x-1\right)-2x\left(x-1\right)-\left(x-2\right)^2\)

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

\(=x^2+x-x^2+4x-4=5x-4\)

2: \(x\left(2+x\right)-\left(x-1\right)\left(3-x\right)-\left(3-x\right)^2\)

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

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

\(=x^2+4x-6\)

3: \(\left(2x-1\right)^2-2\left(2x-1\right)\left(2x-3\right)+\left(3-2x\right)^2\)

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

\(=\left(2x-1-2x+3\right)^2=2^2=4\)

a; Đặt \(A=\left(2x+3\right)\left(2x-3\right)-\left(2x+1\right)^2\)

\(=4x^2-9-4x^2-4x-1\)

=-4x-10

Khi x=1/2 thì \(A=-4\cdot\frac12-10=-2-10=-12\)

b: Đặt \(B=\left(x-2\right)^2-\left(x-1\right)\left(x+1\right)-x\left(1-x\right)\)

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

\(=2x^2-5x+4-x^2+1=x^2-5x+5\)

Khi x=5 thì \(B=5^2-5\cdot5+5=5\)

c: Sửa đề: \(C=\left(2x-1\right)^2+\left(x+1\right)^2+2\left(2x-1\right)\left(x+1\right)\)

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

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

Khi x=-2 thì \(C=9\cdot\left(-2\right)^2=9\cdot4=36\)

d:Đặt D=\(\left(2x-1\right)^2-2\left(2x+3\right)\left(2x+5\right)+\left(2x+5\right)^2\)

\(=4x^2-4x+1-2\left(4x^2+10x+6x+15\right)+4x^2+20x+25\)

\(=8x^2+16x+26-8x^2-32x-30=-16x-4\)

Khi x=2022 thì \(D=-16\cdot2022-4=-32356\)

bạn ghi rõ đề ra được không

a: \(=\left(\dfrac{-\left(x+2\right)}{x-2}-\dfrac{4x^2}{\left(x-2\right)\left(x+2\right)}+\dfrac{x-2}{x+2}\right)\cdot\dfrac{2x^2-x^3}{x^2-3x}\)

\(=\dfrac{-x^2-4x-4-4x^2+x^2-4x+4}{\left(x-2\right)\left(x+2\right)}\cdot\dfrac{x^2\left(2-x\right)}{x\left(x-3\right)}\)

\(=\dfrac{-4x^2-8x}{x+2}\cdot\dfrac{-x}{x-3}\)

\(=\dfrac{-4x\left(x+2\right)}{x+2}\cdot\dfrac{-x}{x-3}=\dfrac{4x^2}{x-3}\)

b: \(=\dfrac{2x-1}{2x+1}:\left(2x-1+\dfrac{2-4x}{2x+1}\right)\)

\(=\dfrac{2x-1}{2x+1}:\dfrac{4x^2-1+2-4x}{2x+1}\)

\(=\dfrac{2x-1}{4x^2-4x+1}=\dfrac{1}{2x-1}\)

c: \(=\left(\dfrac{1}{1-x}-1\right):\left(x+1-\dfrac{2x-1}{x-1}\right)\)

\(=\dfrac{1-1+x}{1-x}:\dfrac{x^2-1-2x+1}{x-1}\)

\(=\dfrac{-x}{x-1}\cdot\dfrac{x-1}{x\left(x-2\right)}=\dfrac{-1}{x-2}\)