Đáp án+Giải thích các bước giải:
`a)x+2sqrtxsqrty+y-zsqrtx-zsqrty`
`=(sqrtx+sqrty)^2-z(sqrtx+sqrty)`
`=(sqrtx+sqrty)(sqrtx+sqrty-z)`
`b)25-4x-4sqrtxsqrty-y`
`=25-(4x+2.2.sqrtxsqrty+y)`
`=25-(2sqrtx+sqrty)^2`
`=(5-2sqrtx-sqrty)(5+2sqrtx+sqrty)`
`c)x-4sqrtxsqrty+4y-z+6sqrtzsqrtt-9t`
`=(sqrtx-2sqrty)^2-(sqrtz-3sqrtt)^2`
`=(sqrtx-2sqrty-sqrtz+3sqrtt)(sqrtx-2sqrty+sqrtz-3sqrtt)`
`d)x+4sqrtx+3`
`=x+3sqrtx+sqrtx+3`
`=sqrtx(sqrtx+3)+sqrtx+3`
`=(sqrtx+3)(sqrtx+1)`
`e)4x+4sqrtx-3`
`=4x-2sqrtx+6sqrtx-3`
`=2sqrtx(2sqrtx-1)+3(2sqrtx-1)`
`=(2sqrtx-1)(2sqrtx+3)`
`f)4x+4sqrtxsqrty-8y`
`=4x-4sqrtxsqrty+8sqrtxsqrty-8y`
`=4sqrtx(sqrtx-sqrty)+8sqrty(sqrtx-sqrty)`
`=4(sqrtx-sqrty)(sqrtx+2sqrty)`
`g)4x-4sqrtxsqrty-9+y`
`=4x-2.2sqrtxsqrty+y-9`
`=(2sqrtx-sqrty)^2-3^2`
`=(2sqrtx-sqrty-3)(2sqrtx-sqrty+3)`
