a: \(C=\left(\dfrac{2x}{\left(x-1\right)\cdot\left(2x-3\right)}-\dfrac{5}{2x-3}\right):\dfrac{3-3x+2}{1-x}\)
\(=\dfrac{2x-5x+5}{\left(x-1\right)\left(2x-3\right)}\cdot\dfrac{-\left(x-1\right)}{-3x+5}\)
\(=\dfrac{-1}{2x-3}\)
b: |2x-3|=7
=>2x-3=7 hoặc 2x-3=-7
=>2x=10 hoặc 2x=-4
=>x=5 hoặc x=-2
Khi x=5 thì \(C=\dfrac{-1}{2\cdot5-3}=\dfrac{-1}{7}\)
Khi x=-2 thì \(C=\dfrac{-1}{-4-3}=\dfrac{1}{7}\)
c: Để C>0 thì 2x-3<0
hay x<3/2
Đúng 2
Bình luận (0)