{[1/(1-x)]+[(1-3x)/(1-x2)]}的极限,x趋于1
问题描述:
{[1/(1-x)]+[(1-3x)/(1-x2)]}的极限,x趋于1
答
[1/(1-x)]+[(1-3x)/(1-x^2)] (这里x^2=x的平方)
=[(1+x)/(1-x^2)]+[(1-3x)/(1-x^2)]
=[(1+x)+(1-3x)]/(1-x^2)
=[2(1-x)]/(1-x^2)
=2/(1+x)
因此,当x趋于1时,所求极限为1.