化简:[(x+1)/(x²-1)]×(x-3)已知ab=﹣1,a+b=2,则式子b/a+a/b=?(上面两个都要答案)

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化简:[(x+1)/(x²-1)]×(x-3)已知ab=﹣1,a+b=2,则式子b/a+a/b=?(上面两个都要答案)
化简:[(x+1)/(x²-1)]×(x-3)
已知ab=﹣1,a+b=2,则式子b/a+a/b=?(上面两个都要答案)

化简:[(x+1)/(x²-1)]×(x-3)已知ab=﹣1,a+b=2,则式子b/a+a/b=?(上面两个都要答案)
:[(x+1)/(x²-1)]×(x-3)
=(x+1)/(x+1)(x-1)×(x-3)
=1/(x-1)×(x-3)
=(x-3)/(x-1)
b/a+a/b=(a²+b²)/ab=[(a²+2ab+b²)-2ab]/ab=[(a+b)²-2ab]/ab=(4+2)/(-1)=-6

(X-3)/(X-1)

化简结果为X-3/x-1
b/a+a/b=-6