Đáp án:
TranMinhHieu334
`a;(x+1)=(x+1)^2`
`<=>(x+1)-(x+1)^2=0`
`<=>(x+1)[1-(x+1)]=0`
`<=>(x+1)(-x)=0`
`<=>-x=0hoặcx+1=0`
`<=>x=0hoặcx=-1` `Vậyx∈{0;-1}`
`b; x^3+x=0`
`<=>x(x^2+1)=0`
`<=>x=0`hoặc `x^2+1=0`
`<=>x=0` hoặc `x^2=-1(VôLý)` `Vậyx∈{0}`
`c;6x(5x-2)-5x+2=0`
`<=>6x(5x-2)-(5x-2)=0`
`<=>(6x-1)(5x-2)=0`
`<=>` `6x-1=0` hoặc `5x-2=0`
`<=>` `6x=1` hoặc `5x=2`
`<=>x `=`1/6` hoặc `x=` `2/5` `Vậy` `x∈{1/6;2/5}`