Cho mình làm lại câu b, nhầm!

b) \(2x-x^2=0\)

\(\Rightarrow x.\left(2-x\right)=0\)

\(\Rightarrow\orbr{\begin{cases}x=0\\2-x=0\end{cases}\Rightarrow\orbr{\begin{cases}x=0\\x=2\end{cases}}}\)

Vậy x = 2 hoặc x = 0

\(B=\frac{637x527-189}{526x637+448}\)

\(B=\frac{637x\left(526+1\right)-189}{526x637+448}\)

\(B=\frac{637x526+637-189}{526x637+448}\)

\(B=\frac{637x526+448}{526x637+448}=1\)

A. Ta có :

8.|x|=8

=>|x| =8:8

=>|x|=1

=>x=1 hoặc x= -1

Vậy x=1 hoặc x= -1

x² + 2x = x(2+x)

1/1000

\(A=x^2+2x\)

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

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

Có :

\(\left(x+1\right)^2\ge0\)

\(\Rightarrow A=\left(x+1\right)^2-1\ge-1\)

\(\Rightarrow A_{min}=-1\Leftrightarrow x=-1\)

3⁰.3¹.3²...3²⁰¹⁶

= 1.3¹.3²...3²⁰¹⁶

= 3¹.3²...3²⁰¹⁶

= 3^1+2+...+2016

= 3^{(1+2016).2016:2}

= 3^2017.1008

= 3^2033136

\(x-\frac{1}{2}-\frac{1}{6}-\frac{1}{12}-\frac{1}{20}-\frac{1}{30}-\frac{1}{42}=1\)

\(x-\left(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+\frac{1}{42}\right)=1\)

\(x-\left(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+\frac{1}{5.6}+\frac{1}{6.7}\right)=1\)

\(x-\left(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+\frac{1}{5}-\frac{1}{6}+\frac{1}{6}-\frac{1}{7}\right)=1\)

\(x-\left(1-\frac{1}{7}\right)=1\)

\(x-\frac{6}{7}=1\)

\(x=1+\frac{6}{7}\)

\(x=\frac{7}{7}+\frac{6}{7}=\frac{13}{7}\)

Vậy \(x=\frac{13}{7}\)

 AxB=0

=> A=0 hoặc B=0

vay dap so la 49 va 11,27 day minh lam bai nay tren violympic roi dung do.

k cho minh nha cac ban.Co bai gi kho cu hoi minh nha.^^