K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

21 tháng 7 2016

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

\(=a^2b-a^2c+b^2c-ab^2+ac^2-bc^2\)

\(=\left(a^2b-bc^2\right)-\left(a^2c-ac^2\right)+\left(b^2c-ab^2\right)\)

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

\(=\left(a-c\right)\left(ab-bc-ac-b^2\right)\)

21 tháng 7 2016

\(1-2a+2bc+a^2-b^2-c^2\)

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

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

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

11 tháng 9 2018

\(1-2a+2bc+a^2-b^2-c^2\)

\(=a^2-2a+1-b^2+2bc-c^2\)

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

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

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

3 tháng 10 2015

1)

b) \(\left(x-z\right)^2-y^2+2y-1\)

\(=\left(x^2-2xz+z^2\right)-\left(y-1\right)^2\)

\(=\left(y-z\right)^2-\left(y-1\right)^2\)

\(=\left[\left(x-z\right)+\left(y-1\right)\right]\cdot\left[\left(x-z\right)-\left(y+1\right)\right]\)

\(=\left(x-z+y-1\right)\cdot\left(x-z-y-1\right)\)

 

22 tháng 9 2020

a) \(P\left(a,b\right)=3a^2-2ab+b^2=3a^2-3ab+ab-b^2\)\(=3a\left(a-b\right)+b\left(a-b\right)=\left(a-b\right)\left(3a+b\right)\)

b) \(P\left(a,b\right)=0\Leftrightarrow\orbr{\begin{cases}a-b=0\\3a+b=0\end{cases}\Leftrightarrow\orbr{\begin{cases}a=b\\a=\frac{-b}{3}\end{cases}}}\)

+) \(a=b\Leftrightarrow M=\frac{a^2+a.a+2a^2}{2a^2-a^2}=4\)

+) \(a=\frac{-b}{3}\Rightarrow M=\frac{\left(\frac{-b}{3}\right)^2+\left(\frac{-b}{3}\right).b+2b^2}{2.\left(\frac{-b}{3}\right)^2-b^2}=\frac{\frac{16}{9}b^2}{\frac{-7}{9}b^2}=\frac{-16}{7}\)

22 tháng 9 2020

cảm ơn Đặng Ngọc Quỳnh nhé :>

a: Sửa đề: \(a^2\left(a+1\right)+b^2\left(b-1\right)-a^2b^2\left(a+b\right)\)

\(=a^3+a^2+b^3-b^2-a^2b^2\left(a+b\right)\)

\(=\left(a+b\right)\left(a^2-ab+b^2\right)+\left(a-b\right)\left(a+b\right)-a^2b^2\left(a+b\right)\)

\(=\left(a+b\right)\left(a^2-ab+b^2+a-b-a^2b^2\right)\)

b: \(=a^m\cdot a^3+2\cdot a^m\cdot a^2+a^m\)

\(=a^m\left(a^3+2a^2+1\right)\)