设f(x)在【a,b】上连续,在(a,b)内可导,且f\'(x)<=0,F(x)=1/(x-a)∫(

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设f(x)在[a,b]上连续,且af(x)在闭区间[a,b]上必有最大值和最小值,设为A与B,则mB+nB

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设函数f(x)在[a,b]上连续,a根据闭区间上连续函数的中间值定理,闭区间上连续函数一定能取到最大值和最小值之间的任何一个值,由于min(x∈[a,b]){f(x)}

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设f(x)在[a,b]上连续,且a[a,b]上连续,由极值大A,Bb

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设f(x)在[a,b]上连续,且a本题是对于任何正整数p,q,否则有问题.构造函数g(x)=pf(c)+qf(d)-(p+q)f(x).当f(c)=f(d)时,g(c)=0,所以存在一点ζ=c,使得pf(c)+qf(d)=(p+q)f(ζ)

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设f(x)在[a,b]上连续,a证明:令k=[pf(c)+qf(d)]/(p+q)无妨设f(c)≤f(d),由于q是正数,所以qf(c)≤qf(d)pf(c)+qf(c)≤pf(c)+qf(d)(p+q)f(c)≤pf(c)+qf(d)①因

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设函数f(x)在[a,b]上连续,a因为f(x)在[a,b]上连续,则f(x)在[x1,xn]上连续.因为闭区间内的连续函数,必有最大值和最小值,分别记为max,min,分别在x=Xmax,x=Xmin处取得不失一般性,可以设x1

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设函数f(x)在[a,b]上连续,在(a,b)内可导且f'(x)F'(x)=【f(x)(x-a)-∫(a,x)f(t)dt】/(x-a)^2=【f(x)(x-a)-f(t0)(x-a)】/(x-a)^2=【f(x)-f(t0)】/(x-a)

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设函数f(x)在[a,b]上连续,在(a,b)上可导且f'(x)

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证明:设f(x)在[a,b]上连续,在(a,b)内可导,(0题目要证明什么?

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设f(x)在[a,b]上连续,在(a,b)上可导(0设g(x)=lnx,因g(x)为初等函数,所以当0

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设函数f(x)在[a,b]上连续,在(a,b)内可导(0令g(x)=x^2在[a,b]上连续,在(a,b)内可导则柯西中值定理:(f(b)-f(a))/(g(b)-g(a))=f'(ξ)/g'(ξ)所以2ξ[f(b)-f(a)]=(b^2-

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设f(x)在[a,b]上连续,在(a,b)内可导,(0证:记g(x)=lnx,显然g(x),f(x)在[a,b]上满足柯西中值定理条件则存在一点ξ∈(a,b)使得[f(b)-f(a)]/[g(b)-g(a)]=f'(ξ)/g'(ξ)即[f(

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设f(x)在[a,b]上连续,在(a,b)内可导(0根据柯西中值定理(f(a)-f(b))/(g(a)-g(b))=f'(e)/g'(e)其中e∈[b,a]本题,可把上方的g(x)看成x^2有:(f(a)-f(b))/(a^2-b^2)=f

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设f(x)在[a,b]上连续,在(a,b)内可导(0令g(x)=x^2,则g'(x)=2x.对f(x)和g(x)使用柯西中值定理,有[f(b)-f(a)]/(b^2-a^2)=f'(ξ)/2ξ,整理一下即可.

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设函数f(x),g(x)在区间[a,b]上连续,且f(a)题目出错了,比如令a=0,b=1f(x)=xg(x)=x+1显然这两条直线没有交点的题目应该是设函数f(x),g(x)在区间[a,b]上连续,且f(a)g(b).证明:在(a,b)内

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设f(x)在[a,b]上连续,且f(b)=a,f(a)=b,证明∫(上b下a)f(x)f'(x)dx=1/2(a²-b²)积分=∫f(x)df(x)=[f(x)]^2/2=[f(b)]^2/2-[f(a)]^2/2=(a

u8BBEf(x)u5728[a,b]u4E0Au8FDEu7EED,u5728(a,b)u5185u53EFu5BFC,f(a)f(b)>0,f(a)f[(a+b)/2]

设f(x)在[a,b]上连续,在(a,b)内可导,f(a)f(b)>0,f(a)f[(a+b)/2]不妨设f(a)>0,f(b)>0,则f((a+b)/2)则F(a)>0,F(b)>0,F(c)零点定理知道,存在c1再在【c1,c2】上用R

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设f(x)在[a,b]上连续,在(a,b)内可导,f(a)f(b)>0,f(a)f[(a+b)/2]0,f(a)f[(a+b)/2]因为f(a)、f(b)同号,f(a)与f[(a+b)/2]异号则根据连续函数介值定理在(a,(a+b)/2)

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设f(x)在[a,b]上连续,在(a,b)内可导,f(a)f(b)>0,f(a)f[(a+b)/2]0,f(a)f[(a+b)/2]不妨设f(a)>0,则f(b)>0,f[(ab)/2]

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设函数f(x)在[a,b]上连续,在(a,b)可导,且f(a)*f(b)>0,f(a)*f((a+b)/2)设F(x)=e^(-kx)f(x)由f(a)*f(b)>0,f(a)*f((a+b)/2)0F(a)*F((a+b)/2)0F(b)