先化简再求值[[(x2+2x+1)/(x+2)]÷[(x2-1)/(x-1)]-x/(x+2)其中x=√3-2

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先化简再求值[[(x2+2x+1)/(x+2)]÷[(x2-1)/(x-1)]-x/(x+2)其中x=√3-2
先化简再求值[[(x2+2x+1)/(x+2)]÷[(x2-1)/(x-1)]-x/(x+2)其中x=√3-2

先化简再求值[[(x2+2x+1)/(x+2)]÷[(x2-1)/(x-1)]-x/(x+2)其中x=√3-2
原式=(x+1)²/(x+2)÷(x+1)(x-1)/(x-1)-x/(x+2)
=(x+1)²/(x+2)÷(x+1)-x/(x+2)
=(x+1)/(x+2)-x/(x+2)
=(x+1-x)/(x+2)
=1/(x+2)
=1/(√3-2+2)
=√3/3

原式=(x+1)²/(x+2)×(x-1)/(x+1)(x-1)-x/(x+2)
=(x+1)/(x+2)-x/(x+2)
=1/(x+2)
当 x=√3-2时
原式=1/√3=√3/3