f(x)在[a,b]连续,在(a,b)二阶连续可导,证明存在c,使f(a)+f(b)-2f((a+b)/2)=1/4f''(c)用泰勒定理,同时因为二阶连续可导要巧妙的用一下介值定理,

f(x)在a到b上连续,f(x) f(x)在（a,b）上具有二阶连续导数又 f'(a)=f'(b)=0 证明：存在u属于(a,b) f(u)f(x)在[a,b]上具有二阶连续导数又 f'(a)=f'(b)=0 证明：存在u属于(a,b),| f''(u)|>=4|f(a)-f(b)|/(b-a)^2 设f(x)在[a,b]上连续,且a 设函数f(x)在[a,b]上连续,a 设f(x)在[a,b]上连续,且a f(x)在[a,b]上连续a 若函数f(x)在[a,b]上连续,a f(x)在（a,b)内连续且a< x1 若f(x)在[a,b]上连续,a f(x)在[a,b]上连续,a 设f(x)在[a,b]上连续,且a 设f(x)在[a,b]上连续,a 设函数f(x)在[a,b]上连续,a 若函数f(x)在[a,b]上连续,a f(x)在[a,b]连续且可导,a 若函数f(x)在[a,b]上连续,a f(x)在（a,b）上具有二阶连续导数又 f'(a)=f'(b)=0 证明：存在u属于(a,b) f(u) 设函数f(x)在[a,b]上连续,在(a,b)内可导且f'(x)