Question

Answer 1

a: ĐKXĐ: x<>1; x<>3; x<>-3

\(P=\dfrac{x-1+1}{x-1}:\dfrac{x^2-7+x-3-x+1}{\left(x-3\right)\left(x-1\right)}\)

\(=\dfrac{x}{x-1}\cdot\dfrac{\left(x-1\right)\left(x-3\right)}{x^2-9}=\dfrac{x}{x+3}\)

b: |x+2|=5

=>x+2=5 hoặc x+2=-5

=>x=-7(nhận) hoặc x=3(loại)

Khi x=-7 thì \(P=\dfrac{-7}{-7+3}=\dfrac{-7}{-4}=\dfrac{7}{4}\)

c: Để P>1 thì P-1>0

=>\(\dfrac{x-x-3}{x+3}>0\)

=>x+3<0

=>x<-3