Giải phương trình: 1) {x3+√x2+1+√x2−y2=y3+√y2+1x3+2y+3−2√y3−1=(x2+2x+3)√xy−y+1
2) {3√x3−3√x+1−5+x2y=x−1+(y−1)3(x−y)[(x+y+1)2+1]=2y(x2−xy+x−y)
3) {√2x2−6xy+5y2+√2x2+2xy+13y2=2(x+y)(x+2y)√x+2−4y2√y=8y4√y−2√x+2
4) x√33x2−32x+8+2(2x−1)√20x2−12x+1=1.
5)
{(1−y)√x2+2y2=x+2y+3xy√y+1+√x2+2y2=2y−x