高数等价无穷小问下能不能用等价无穷小来计算,lim sin(1-x)^2 / x^4-2x^2+1x-1lim((1+(sin_数学解答

高数等价无穷小
问下能不能用等价无穷小来计算,
lim sin(1-x)^2 / x^4-2x^2+1
x-1
lim((1+(sinx)^2+x)^1/2) / (1+2x^2)^1/2 -1
x-0
lim x^2(1-cos(1/x))
x-无穷

人气：455 ℃　时间：2020-02-19 17:06:46

解答

1,x ->1,lim sin(1-x)² / x^4-2x^2+1=lim (1-x)² / x^4-2x^2+1=lim (1-x)² / (1-x)²(1+x)²=lim 1 / (1+x)²=1/42,x ->0,lim [ (1+2x^2)^1/2 -1] / ((1+(sinx)^2+x)^1/2) =0/1=0,原极限...