lim x→1 (x³-3x+2)/(1-x²)麻烦给写下过程

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limx→1(x³-3x+2)/(1-x²)麻烦给写下过程limx→1(x³-3x+2)/(1-x²)麻烦给写下过程limx→1(x³-3x+2)/(

lim x→1 (x³-3x+2)/(1-x²)麻烦给写下过程
lim x→1 (x³-3x+2)/(1-x²)
麻烦给写下过程

lim x→1 (x³-3x+2)/(1-x²)麻烦给写下过程
x³-3x+2=(x³-x)-(2x-2)=x(x^2-1)-2(x-1)=x(x+1)(x-1)-2(x-1)=(x-1)(x^2+x-2)
lim x→1 (x³-3x+2)/(1-x²)=lim x→1 (x-1)(x^2+x-2)/(1-x)(1+x)
=lim x→1 -(x^2+x-2)/(1+x)=0

用罗比达法则:
lim[(x³-3x+2)/(1-x²)] (0/0型)
=lim[3(x-1)/(-2x)]
=3×(1-1)/(-2×1)
=0.