Question

Answer 1

1:

a: =>2x-1=0 hoặc x+1=0

=>x=1/2 hoặc x=-1

b; =>x-1=0 hoặc 3x-1=0

=>x=1/3 hoặc x=1

c: ĐKXĐ: x<>2; x<>-1

PT sẽ là \(\dfrac{x-2-5x-5}{\left(x-2\right)\left(x+1\right)}=\dfrac{15}{\left(x+1\right)\left(x-2\right)}\)

=>-4x-7=15

=>-4x=22

=>x=-11/2

d: ĐKXĐ: x<>-2; x<>2

PT =>\(\left(x-1\right)\left(x-2\right)-x\left(x+2\right)=5x-2\)

=>x^2-3x+2-x^2-2x=5x-2

=>-5x+2=5x-2

=>-10x=-4

=>x=2/5(nhận)

2:

a: =>7(x-2)-12>4(x+1)

=>7x-14-12>4x+4

=>7x-26>4x+4

=>3x>30

=>x>10

b; =>3(x+2)-1<=7(3x+1)

=>3x+6-1<=21x+7

=>3x+5<=21x+7

=>-18x<=2

=>x>=-1/9