①[1-1/(x-1)][x/(x+1)+1]÷[1-3x/(1-x^2)] ②计算:[x^2-4/(x^2-4x+4)-x-2/_数学解答

①[1-1/(x-1)][x/(x+1)+1]÷[1-3x/(1-x^2)] ②计算:[x^2-4/(x^2-4x+4)-x-2/(x+2)]÷x/(x-2)
③2/（a+1)-a-2/(a^2-1)÷a^2-2a/（a^2-2a+1）

人气：297 ℃　时间：2020-02-05 13:07:35

解答

①[1-1/(x-1)][x/(x+1)+1]÷[1-3x/(1-x^2)] =[(x-1-1)/(x-1)][(x+x+1)/(x+1)]÷[(1-x^2-3x)/(1-x^2)]=[(x-2)/(x-1)][(2x+1)/(x+1)]÷[(1-x^2-3x)/(1-x^2)]=[(2x^2+x-4x-2)/(x^2-1)]*[(1-x^2)/(1-x^2-3x)]=[(2x^2-3x-...