设ab>0,f(x)在[a,b]上连续,在(a,b)内可导,证明:存在ε∈(a,b),使得设f(x)在[a,b]上连续,在(a,b)设f(x)在[a,b]上连续,在(a,b)内连续可导,x。∈(a,b)是f(x)的唯一驻点.若f(x。)是极小值,证明:x∈(a,x。)时,fˊ(x)<0;x∈(x。,b)时,fˊ(x)>0
举一反三
- 设f(x)在[a,b]上连续,且f(x)不恒等于零,证明∫(a,b)[f(x)]²dx>0
- 设f(x)在[a,b]上连续,在(a,b)内可导(0<a<b),证明:存在ξ,η∈(a,b),使得f′(ξ)=f′(η)abη2.
- 设f(x)及g(x)在[a,b]上连续,证明:若在[a,b]上,f(x)≥0,且。
- 设f(x),g(x)在[a,b]上二阶可导,g""(x)≠0,f(a)=f(b)=g(a)=g(b)=0.证明:设f(x),g(x)在[a,b]上二阶可导,g""(x)≠0,f(a)=f(b)=g(a)=g(b)=0.证明:
- 设函数f(x),g(x)在[a,b]上连续,在(a,b)内可导,且g’(x)≠0,