Bài 1: Giải phương trình
a. \(\dfrac{x+1}{2004}+\dfrac{x+2}{2003}=\dfrac{x+3}{2002}+\dfrac{x+4}{2001}\)
b \(\dfrac{201-x}{99}+\dfrac{203-x}{97}+\dfrac{205-x}{95}+3=0\)
c \(2x^2-6x+1=0\)
d \(x^3+x=2\)
Bài 2: Giải phương trình chứa dấu giá trị tuyệt đối
a \(\left|x+3\right|=3x-1\)
b \(\left|-2x\right|=x^2\)
Bài 1/a
Bài 1.
b) \(\dfrac{201-x}{99}+\dfrac{203-x}{97}+\dfrac{205-x}{95}+3=0\)
\(\Leftrightarrow\dfrac{201-x}{99}+1+\dfrac{203-x}{97}+1+\dfrac{205-x}{95}+1=0\)
\(\Leftrightarrow\dfrac{300-x}{99}+\dfrac{300-x}{97}+\dfrac{300-x}{95}=0\)
\(\Leftrightarrow\left(300-x\right)\left(\dfrac{1}{99}+\dfrac{1}{97}+\dfrac{1}{95}\right)=0\)
\(\Leftrightarrow300-x=0\) (vì \(\dfrac{1}{99}+\dfrac{1}{97}+\dfrac{1}{95}\ne0\))
\(\Leftrightarrow x=300\)
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