a) \(8y^3+1\)

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

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

b) \(y^3-8\)

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

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

`8y^3 + 1 = (2y+1)(4y^2 - 2y + 1)`

`y^3 -8 =(y-2)(y^2+2y+4)`

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

b: \(x^3-\dfrac{1}{8}=\left(x-\dfrac{1}{2}\right)\left(x^2+\dfrac{1}{2}x+\dfrac{1}{4}\right)\)

c: \(8x^3+y^3=\left(2x+y\right)\left(4x^2-2xy+y^2\right)\)

a) \(\left(x+3\right)\cdot\left(x^2-3x+9\right)\)

b) \(\left(x-\dfrac{1}{2}\right)\cdot\left(x^2+\dfrac{1}{2}x+\dfrac{1}{4}\right)\)

c) \(\left(2x+y\right)\cdot\left(4x^2-2xy+y^2\right)\)

\(a,27-x^3\)

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

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

Các câu còn lại lm tương tự nhé.

hok tốt!

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

b)  \(8x^3+0,001=\left(2x+0,1\right)\left(4x^2-0,2x+0,01\right)\)

c)  \(\frac{x^3}{125}-\frac{y^3}{27}=\left(\frac{x}{5}-\frac{y}{3}\right)\left(\frac{x^2}{25}+\frac{xy}{15}+\frac{y^2}{9}\right)\)

p/s: chúc bạn học tốt

a: \(\left(x+y+z\right)^2-\left(y+z\right)^2\)

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

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

b: \(\left(x+3\right)^2+4\left(x+3\right)+4\)

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

\(=\left(x+5\right)\left(x+5\right)\)

c: \(25+10\left(x+1\right)+\left(x+1\right)^2\)

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

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

\(27-x^3\)

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

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

\(8x^3+0,001\)

\(=\left(2x\right)^3+\left(\dfrac{1}{10}\right)^3\)

\(=\left(2x+\dfrac{1}{10}\right)\left(4x^2-2x\dfrac{1}{10}+\left(\dfrac{1}{10}\right)^2\right)\)

\(=2\left(x+\dfrac{1}{5}\right)\left(4x^2-\dfrac{1}{5}x+\dfrac{1}{100}\right)\)

\(\dfrac{x^3}{125}-\dfrac{y^3}{27}\)

\(=\left(\dfrac{x}{5}\right)^3-\left(\dfrac{y}{3}\right)^3\)

\(=\left(\dfrac{x}{5}-\dfrac{y}{3}\right)\left[\left(\dfrac{x}{5}\right)^2+\dfrac{x}{5}.\dfrac{y}{3}+\left(\dfrac{y}{3}\right)^2\right]\)

\(=\left(\dfrac{x}{5}-\dfrac{y}{3}\right)\left(\dfrac{x^2}{25}+\dfrac{xy}{15}+\dfrac{y^2}{9}\right)\)