![](https://rs.olm.vn/images/avt/0.png?1311)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(3x^2-3xy-5x+5y=3x\left(x-y\right)-5\left(x-y\right)=\left(3x-5\right)\left(x-y\right)\\ x^3-3x^2-4x+12=x^2\left(x-3\right)-4\left(x-3\right)=\left(x-2\right)\left(x+2\right)\left(x-3\right)\\ 45+x^3-5x^2-9x=x^2\left(x-5\right)-9\left(x-5\right)=\left(x-3\right)\left(x+3\right)\left(x-5\right)\)
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(H=3x-5-3x^2\)
\(=-3\left(x^2-x+\frac{5}{3}\right)\)
\(=-3\left(x^2-2.x.\frac{1}{2}+\frac{1}{4}+\frac{17}{12}\right)\)
\(=-3\left(\left(x-\frac{1}{2}\right)^2+\frac{17}{12}\right)\)
\(=\frac{-17}{4}-3\left(x-\frac{1}{2}\right)^2\le\frac{-17}{4}\)
\(MAXH=\frac{-17}{4}\Leftrightarrow x-\frac{1}{2}=0\Rightarrow x=\frac{1}{2}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
p) \(x^3-3x^2+3x-1+2\left(x^2-x\right)\\ =\left(x^3-1\right)-\left(3x^2-3x\right)+2x\left(x-1\right)\\ =\left(x-1\right)\left(x^2+x+1\right)-3x\left(x-1\right)+2x\left(x-1\right)\\ =\left(x-1\right)\left(x^2+x+1-3x+2x\right)\\ =\left(x-1\right)\left(x^2+1\right)\)
p:Ta có: \(x^3-3x^2+3x-1+2\left(x^2-x\right)\)
\(=\left(x-1\right)^3+2x\left(x-1\right)\)
\(=\left(x-1\right)\left(x^2-2x+1+2x\right)\)
\(=\left(x-1\right)\left(x^2+1\right)\)
![](https://rs.olm.vn/images/avt/0.png?1311)
x( a - b ) - a + b = x( a - b ) - ( a - b ) = ( a - b )( x - 1 )
a( x - y ) - x + y = a( x - y ) - ( x - y ) = ( x - y )( a - 1 )
mấy ý kia không sửa được nữa nên nghỉ:)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(x^2+3x-10=x^2+5x-2x-10=x\left(x+5\right)-2\left(x+5\right)=\left(x-2\right)\left(x+5\right)\)
Ta có.452 + 402 - 152 + 80.45 = (452 + 2×40×45 + 402) - 152 = 852 - 152 = (85 - 15)(85 + 15) = 70×100 = 7000