求证limx->+∞ f(x)=0f(x)=∫{0,1}lnt*t^x/(t-1)*dt

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求证limx->+∞f(x)=0f(x)=∫{0,1}lnt*t^x/(t-1)*dt求证limx->+∞f(x)=0f(x)=∫{0,1}lnt*t^x/(t-1)*dt求证limx->+∞f(x)

求证limx->+∞ f(x)=0f(x)=∫{0,1}lnt*t^x/(t-1)*dt
求证limx->+∞ f(x)=0
f(x)=∫{0,1}lnt*t^x/(t-1)*dt

求证limx->+∞ f(x)=0f(x)=∫{0,1}lnt*t^x/(t-1)*dt
f(x)=∫{0,1/2}lnt*t^x/(t-1)*dt+∫{1/2,1}lnt*t^x/(t-1)*dt=∫{0,1/2}[t/(t-1)*lnt]*t^(x-1)dt+∫{1/2,1}[lnt/(t-1)]*t^xdt=A(x)+B(x).
在(0,1/2)内,|t/(t-1)*lnt|

原来是lnt