`(15xx8-10xx7)/(5xx6+20xx3)`

`=(5xx3xx8-5xx2xx7)/(5xx6+5xx4xx3)`

`=(5xx24-5xx14)/(5xx6+5xx12)`

`=(5xx(24-14))/(5xx(6+12))`

`=10/(18)`

`=5/9`

ava nèo :?

ai biếc rì đou :]

`((-2)^2 .15^4)/(8^2 .125)`

`=(2^2 .3^4 .5^5)/((2^3)^2 .5^3)`

`=(2^2 .3^4 .5^2)/(2^6)`

`=(3^4 .5^2)/(2^4)`

`=(81.25)/16`

`=2025/16`

`x xx7+x xx12=266`

`=>x xx(7+12)=266`

`=>x xx19=266`

`=>x=266:19`

`=>x=14`

Vậy `x=14`

\(a)3-2\sqrt{3}\\=3-2\sqrt{3}.1+1\\=(\sqrt{3}-1)^2\\b)2\sqrt{3}-\sqrt{6}\\=2\sqrt{3}-\sqrt{2}\sqrt{3}\\=\sqrt{2}\sqrt{3}(\sqrt{2}-1)\\=\sqrt{6}(\sqrt{2}-1)\)

lỗi lệnh =)

they informed us that they would arrive on may 20th

`->`We were informed that they would arrive on may20th

-Bđ thì qhđ

`+)x>1`

`<=>x-1>0`

`(\sqrt{x^2 -2x+1})/(x-1)`

`=(\sqrt{(x-1)^2})/(x-1)`

`=(|x-1|)/(x-1)~`

`=(x-1)/(x-1)`

`=1`

Vậy...

`+)x<2`

`<=>x-2<0`

`|x-2|+(\sqrt{x^2-4x+4})/(x-2)`

`=2-x+(\sqrt{(x-2)^2})/(x-2)`

`=2-x+(|x-2|)/(x-2)`

`=2-x+(2-x)/(-(2-x))`

`=2-x-1`

`=1-x`

Vậy...