4.2x+1+x√(x2+2)+(x+1)√(x2+2x+3)=0
[x√(x2+2)+(x+1)√(x2+2x+3)]2=(2x+1)2
2(x4+2x3+6x2+2x+1)=-2x(x+1)√[(x2+2)(x2+2x+3)]
(x2+x+1)4=x2(x+1)2(x2+2)(x2+2x+3)
x8+4x7+10x6+16x5+19x4+16x3+10x2+4x+1=x8+4x7+10x6+16x5+19x4+16x3+6x2
.......4x2+4x+1=0,(2x+1)2=0,x=-0.5
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