yonphee
幼苗
共回答了15个问题采纳率:93.3% 举报
[(x+2)/(x²-2x) – (x-1)/(x²-4x+4)]÷(x²-16)/(x²+4x)
=[(x+2)/x(x-2) – (x-1)/(x-2)²]÷[(x+4)(x-4)/x(x+4)]
={[(x+2)(x-2)-x(x-1)]/x(x-2)²}÷[(x-4)/x]
=[(x²-4-x²+x)/x(x-2)²]×[x/(x-4)]
=[(x-4)/x(x-2)²]×[x/(x-4)]
=1/(x-2)²
=1/(2+√2-2)²
=1/2
1年前
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