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设f(x)在区间[0,1]上连续,证明:
设f(x)在区间[0,1]上连续,证明:<img src='https://img2.soutiyun.com/ask/2020-12-15/976873792952469.png' />
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设f(x)在[a,b]上连续,在(a,b)内连续可导,x<sub>0</sub>∈(a,b)是f(x)的唯一驻点。若f(x<sub>0</sub>)是极小值,证明:x∈(a,x<sub>0</sub>)时,f'(x)<0;x∈(x<sub>0</sub>,b)时,f'(x)>0。
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设f(x)在上连续,且,证明
设f(x)在<img src='https://img2.soutiyun.com/ask/2021-02-02/981108508925152.png' />上连续,且<img src='https://img2.soutiyun.com/ask/2021-02-02/98110851624057.png' />,证明
<img src='https://img2.soutiyun.com/ask/2021-02-02/981108523349977.png' />
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设I为一无穷区间,函数f(x)在I上连续,I内可导,试证明:如果在I的任一有限的子区间上,f'(x)≥0(或f'(x)≤0),且等号仅在有限多个点处成立,那么f(x)在区间I上单调增加(或单调减少).
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设函数f(x)在[a,b]上连续,且f(x)>0,证明:在(a,b)内存在一个ξ,使得
设函数f(x)在[a,b]上连续,且f(x)>0,证明:在(a,b)内存在一个ξ,使得
<img src='https://img2.soutiyun.com/ask/2021-01-14/979465674691464.png' />
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设(x)在[a,b]上连续,在(a,b)内可导且f'(x)≤0,证明在(a,b)内有F'(x)≤0.
设(x)在[a,b]上连续,在(a,b)内可导且f'(x)≤0,
<img src='https://img2.soutiyun.com/ask/2020-08-06/965576645302938.png' />
证明在(a,b)内有F'(x)≤0.
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设f(x)在[a, b]上连续,在(a, b)内可导且f'(x)≤0,证明:在(a, b)内有F'(a)≤0
设f(x)在[a, b]上连续,在(a, b)内可导且f'(x)≤0,
<img src='https://img2.soutiyun.com/ask/2020-12-14/976805726019948.png' />
证明:在(a, b)内有F'(a)≤0
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设函数f(x)在[0,1]上连续,且f(0)= f(1),证明一定存在x∈(0,)使得f(x<sub>0</sub>)= f(x<sub>0</sub>+).
设函数f(x)在[0,1]上连续,且f(0)= f(1),证明一定存在x∈(0,<img src='https://img2.soutiyun.com/ask/2020-12-20/977320815878019.png' />)使得f(x<sub>0</sub>)= f(x<sub>0</sub>+<img src='https://img2.soutiyun.com/ask/2020-12-20/977320902712985.png' />).
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设f(x)在[a,b]上连续,在(a,b)内可导,且f(a)=f(b)=0.证明:存在ξ∈(a,b),使f'(ξ)=f(ξ)成立.
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设f(x)在[a,b]上连续,任取p>0,q>0,证明:存在ξ∈[a,b],使得pf(a)+qf(b)=(p+q)f(ξ)。
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设f(x)在区间[a,b]上连续,g(x)在区间[a,b]上连续且不变号.证明至少存在一点x[a,b],使下式成立
设f(x)在区间[a,b]上连续,g(x)在区间[a,b]上连续且不变号.证明至少存在一点
x<img src='https://img2.soutiyun.com/ask/2020-12-04/97592702964699.png' />[a,b],使下式成立
<img src='https://img2.soutiyun.com/ask/2020-12-04/975927090499471.png' />
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设f(x)在区间I上连续,并且在I上仅有惟一的极值点x<sub>0</sub>证明:若x<sub>0</sub>是f的极大(小)值点,则x<sub>0</sub>必是f(x)在I上的最大(小)值点.
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设函数f(x)在[0,1]上连续,在(0,1)内可导,且证明在(0,1)内存在一点ξ,使f'(ξ)=0。
设函数f(x)在[0,1]上连续,在(0,1)内可导,且<img src='https://img2.soutiyun.com/ask/2020-08-07/965639441738848.png' />证明在(0,1)内存在一点ξ,使f'(ξ)=0。
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设D为平面有限闭区域,f(x,y),g(x,y)在D上连续,且g(x,y)≥0,证明:存在(ξ,η)∈D,使得
设D为平面有限闭区域,f(x,y),g(x,y)在D上连续,且g(x,y)≥0,证明:存在(ξ,η)∈D,使得<img src='https://img2.soutiyun.com/ask/2020-12-08/976284059780651.jpg' />
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设f(x)在[a,b]上连续,f'(x)在(a,b)内是常数,证明f(x)在[a,b]上的表达式为f(x)=Ax+B,其中A,B是常数.
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设函数,其中函数g(x)在(-∞,+∞)上连续,且g(1)=5,,证明,并计算f''(1)和F'''
设函数<img src='https://img2.soutiyun.com/ask/2020-12-16/976976603992918.png' />,其中函数g(x)在(-∞,+∞)上连续,且
g(1)=5,<img src='https://img2.soutiyun.com/ask/2020-12-16/976976616554637.png' />,证明<img src='https://img2.soutiyun.com/ask/2020-12-16/976976676821084.png' />,并计算f''(1)和F'''(1).
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设(1)证明f(x)在[0,+∞)上可导,且一致连续;(2)证明反常积分发散。
设<img src='https://img2.soutiyun.com/ask/2021-01-28/980692750486118.png' />
(1)证明f(x)在[0,+∞)上可导,且一致连续;
(2)证明反常积分<img src='https://img2.soutiyun.com/ask/2021-01-28/980692795149672.png' />发散。
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设f在可求面积的区域D上连续.证明:若在D上(x,y)≥0,f(x,y)≠0,则
设f在可求面积的区域D上连续.证明:若在D上(x,y)≥0,f(x,y)≠0,则<img src='https://img2.soutiyun.com/ask/2021-01-06/978805614690088.png' />
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设f(x,y)在[a,b;c,∞)上连续,且保持同一符号,y)dy在[a,b]上连续,证明:
设f(x,y)在[a,b;c,∞)上连续,且保持同一符号,<img src='https://img2.soutiyun.com/ask/2021-01-06/978797314201327.png' />y)dy在[a,b]上连续,证明:
<img src='https://img2.soutiyun.com/ask/2021-01-06/978797330365252.png' />
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设函数f(x)在[a,b]上连续,a≤x<sub>1</sub><x<sub>2</sub><...<x<sub>n</sub>≤b,证明在[a,b]中必有ξ,使得
设函数f(x)在[a,b]上连续,a≤x<sub>1</sub><x<sub>2</sub><...<x<sub>n</sub>≤b,证明在[a,b]中必有ξ,使得
<img src='https://img2.soutiyun.com/ask/2020-12-15/976895957488208.png' />
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设f(x)在[a,b]上连续,在(a,b)内可导且f'(x)≤0,证明在(a,b)内有F'(x)<0.
设f(x)在[a,b]上连续,在(a,b)内可导且f'(x)≤0,
<img src='https://img2.soutiyun.com/ask/2020-12-04/975925572077622.png' />
证明在(a,b)内有F'(x)<0.
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设f(x)在[a,a+2a]上连续,证明:存在x∈[a,a+a],使得
设f(x)在[a,a+2a]上连续,证明:存在x∈[a,a+a],使得
<img src='https://img2.soutiyun.com/ask/2020-11-28/975434185090508.png' />
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设函数f在[0,2a]上连续,且f(0)=f(2a)证明:存在点x<sub>0</sub>∈[0,a],使得f(x<sub>0</sub>)=f(x<sub>0</sub>+a)
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设函数f(x),g(x)在[a,b]上连续,且f(a)>g(a),f(b)<g(b),证明在(a,b)内曲线y=f(x)与y=g(x)至少有一个交点。