Question

1) Tìm x biết : ||2x+1|-2| = 3

 

Answer 1

TH1: |2x+1|-2=(-3)
=> |2x+1|=(-3)+2
=> |2x+1|=(-1) (VN) vì |2x+1| >=0
TH2: |2x+1|-2=3
=> |2x+1|=3+2
=> |2x+1|=5
      * 2x+1=(-5)
     => 2x=(-5)+(-1)
      => 2x=(-6)
      => x=(-3)
      ** 2x+1=5
      => 2x=5-1
      => 2x=4
      => x=2