giải các phương trình sau
1) x+\(\sqrt{4-x^2}\)=2+2x\(\sqrt{4-x^2}\)
2) \(\sqrt{2x^2+11x+19}\)+\(\sqrt{2x^2+5x+1}\)=3.( x+1)
3) \(\sqrt{2x^2+7x+10}\)+\(\sqrt{2x^2+x+4}\)= 3.(x+1)
4) \(\sqrt{4x^2+5x+1}\)- 2\(\sqrt{x^2-x-1}\)= 9x-3
5) 2x2+4=3.\(\sqrt{x^3+1}\)
6) 2x2+5x-1=7\(\sqrt{x^3-1}\)