好人来,小弟求答!先化简,再求值:(X-1)分之X-(X+1)分之X除以(1-X)分之2X,其中X等于根号3.

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好人来,小弟求答!先化简,再求值:(X-1)分之X-(X+1)分之X除以(1-X)分之2X,其中X等于根号3.

好人来,小弟求答!先化简,再求值:(X-1)分之X-(X+1)分之X除以(1-X)分之2X,其中X等于根号3.
好人来,小弟求答!先化简,再求值:(X-1)分之X-(X+1)分之X除以(1-X)分之2X,其中X等于根号3.

好人来,小弟求答!先化简,再求值:(X-1)分之X-(X+1)分之X除以(1-X)分之2X,其中X等于根号3.
=x/(x-1)-x/(x+1)×(1-x)/2x
=x/(x-1)+(x-1)/2(x+1)
=[2x(x+1)+(x-1)²]/2(x-1)(x+1)
=(3x²+1)/2(x²-1) x²=3
=(9+1)/2(3-1)
=5/2

答案是负二分之一

2分之1-根号3

原式=x/(x-1)-(1-x)/2x+2
=x(1-x)/[(x-1)(2x+2)]
=(x²-x)/(2x²-2x-3)
当x=√3时,x²=3,原式=(3-√3)/(2*6-2*√3-3)
=(3-√3)/(9-2√3)
答:所求式的值为(3-√3)/(9-2√3)

X/(X-1)-X/(X+1)÷2X/(1-X)
=X/(X-1)+(2X^2)/[(X+1)(X-1)]
=[X(X+1)]/[(X+1)(X-1)]+(2X^2)/[(X+1)(X-1)]
=(3X^2+X)/[(X+1)(X-1)]
=(3X^2+X)/(X^2-1)
当X=根3时
原式=(9+√3)/(3-1)=9/2+√3/2.