Question

Tìm x biêt 

| 3x-1|=(x+1)

 

Answer 1

3x-1=0 suy ra x=0,₍₃₎

chia khoảng để giải:tự làm

nếu x<0,33 btvt

3x+1=x=1

3x-x=1-1

2x=0

x= rỗng

Nếu x>0,33 btvt

3x-1=x+1

3x-x=1+1

2x=2

x=1(nghiêm)

Answer 2

| 3x-1|=(x+1)

=>| 3x-1|=± x+1

Th1:3x-1=x+1                              Th2:3x-1=-x+1

=>3x-x=1+1                                =>3x-1=-(x-1)

=>2x=2                                      =>3x-1=1-x

=>x=1                                        =>3x+x=1+1

                                                  =>4x=2

                                                  =>x=\(\frac{1}{2}\)

Answer 3

TH1: 3x-1>=0 =>x>=\( {1 \over 3}\)

3x-1=x+1

3x-x=1+1

2x=2

x=1( thỏa mãn x>=\( {1 \over 3}\))

TH2: 3x-1<0 =>x<\( {1 \over 3}\)

-(3x-1)=x+1

-3x+1=x+1

-3x-x=1-1

-4x=0

x=0( thỏa mãn x<\( {1 \over 3}\))

Vậy x=1 hoặc x=0 thì |3x-1|=x+1

Answer 4

x=1 hoặc x=0