设f(x)连续,且f(0)<>0,求极限lim(x~0)∫x上0下(x-t)f(t)dt⼀x∫x上0下(x-t)dt

2024-11-01 08:40:39
推荐回答(1个)
回答1:

lim(x~0)∫(0,x)(x-t)f(t)dt/x∫(0,x)(x-t)dt
=lim(x~0)[x∫(0,x)f(t)dt-∫(0,x)tf(t)dt]/[x^2∫(0,x)dt-x∫(0,x)tdt]
=lim(x~0)[∫(0,x)f(t)dt+xf(x)-xf(x)]/[3x^2/2]
=lim(x~0)[∫(0,x)f(t)dt]/[3x^2/2]
=lim(x~0)[f(x)]/3x=∞