-
设二次函数f(x)=ax
2
+bx+c(a>O),方程f(x)-x=O的两个根x
1
,x
2
满足
https://assets.asklib.com/psource/2016030616072289666.jpg
。
(1)当x∈(0,x
1
)时,证明x;
(2)设函数f(x)的图象关于直线x=x
0
对称,证明
https://assets.asklib.com/psource/2016030616072314233.jpg
。
-
设f(x),g(x)在[0,1]上的导数连续,且f(0)=0,f′(x)≥0,g′(x)≥0。证明:对任何a∈[O,1],有https://assets.asklib.com/psource/2016030616211474049.jpg
-
设ϕ(x)为可微函数y=f(x)的反函数,且f(1)=0,证明:
设ϕ(x)为可微函数y=f(x)的反函数,且f(1)=0,证明:
<img src='https://img2.soutiyun.com/ask/2021-01-14/979465639213434.png' />
-
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' />
-
设f(x)在(-∞,+∞)内有定义,证明:f(x)+f(-x)为偶函数,而f(x)-f(-x)为奇函数。
-
设f(x)∈C(1)(-∞,+∞),并对任意x及h均有 f(x+h)-f(x)≡hf&39;(x)(1) 证明f(x)=ax+b.此处a、b是常数
设f(x)∈C<sup>(1)</sup>(-∞,+∞),并对任意x及h均有
f(x+h)-f(x)≡hf&39;(x)(1)
证明f(x)=ax+b.此处a、b是常数
-
设f(x)为[-a,a]上的连续函数,证明:(1)若f(x)是偶函数,则是[-a,a]上的奇函数;(2)若f(x)是奇函数
设f(x)为[-a,a]上的连续函数,证明:
(1)若f(x)是偶函数,则<img src='https://img2.soutiyun.com/ask/2020-10-12/971368555517115.png' />是[-a,a]上的奇函数;
(2)若f(x)是奇函数,则<img src='https://img2.soutiyun.com/ask/2020-10-12/971368586317876.png' />是[-a,a]上的偶函数。
-
设f(x)为[0,1]上的非负单调非增连续函数(即当x<y时,f(x)≥f(y)).利用积分中值定理证明:对于0<a<
设f(x)为[0,1]上的非负单调非增连续函数(即当x<y时,f(x)≥f(y)).利用积分中值
定理证明:对于0<a<β<1.有下面的不等式成立
<img src='https://img2.soutiyun.com/ask/2020-11-30/975612485146551.png' />
-
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' />).
-
设函数f(x)和g(x)在[0,1]上有连续导数,且f(0)=0,f'(x)≥0,g'(x)≥0.证明:对任何a∈[0,1]
设函数f(x)和g(x)在[0,1]上有连续导数,且f(0)=0,f'(x)≥0,g'(x)≥0.证明:对任何a∈[0,1],都有
<img src='https://img2.soutiyun.com/ask/2020-12-13/97672399961901.png' />
-
设f(x)∈C[a,b],且f"(x)>0,取x<sub>i</sub>∈[a,b](1≤i≤n),设k<sub>i</sub>>0(1≤i≤n)且。证明:
设f(x)∈C[a,b],且f"(x)>0,取x<sub>i</sub>∈[a,b](1≤i≤n),设k<sub>i</sub>>0(1≤i≤n)且<img src='https://img2.soutiyun.com/ask/2020-12-04/975950635482167.jpg' />。证明:<img src='https://img2.soutiyun.com/ask/2020-12-04/975950645106717.jpg' />
-
设m<sub>1</sub>(x),…,ms(x)为一组两两互素的多项式,证明:对任何的多项式f<sub>1</sub>(x),…,fs(x),都存在多项式F(x);使F(x)=f<sub>i</sub>(x) (mod mi(x)),i=1,…,s
-
下列函数中有一个不是f(x)=1/x的原函数,它是[ ].<br/>A.F(x)=ln |x|<br/>B.F(x)=In |Cx| (C是不为零且不为1的常数)<br/>C.F(x)=Cln |x| (C是不为零且不为1的常数)<br/>D.F(x)=ln |x|+C (C是不为零的常数)
A:F(x)=In
B:F(x)=Cln
C:F(x)=ln
-
设(f(x)=ln(1+x),x∈(-1,1).由拉格朗日中值定理得: .使得ln(1+x)-In(1+0)=证明:
设(f(x)=ln(1+x),x∈(-1,1).由拉格朗日中值定理得:<img src='https://img2.soutiyun.com/ask/2021-01-13/97939236664681.png' />.<img src='https://img2.soutiyun.com/ask/2021-01-13/979392378464486.png' />使得ln(1+x)-In(1+0)=<img src='https://img2.soutiyun.com/ask/2021-01-13/979392393557349.png' />证明:<img src='https://img2.soutiyun.com/ask/2021-01-13/979392405881054.png' />
-
设f"(x)存在,求下列函数的二阶导数;(1) y=f(x<sup>2</sup>);(2)y=ln[f(x)].
设f"(x)存在,求下列函数的二阶导数<img src='https://img2.soutiyun.com/ask/2020-11-10/973871310253584.png' />;
(1) y=f(x<sup>2</sup>);(2)y=ln[f(x)].
-
设f<sub>1</sub>(x), f<sub>2</sub>(x); g<sub>1</sub>(x), g<sub>2</sub>(x)都是数域K上的多项式,共中f<sub>1</sub>(x)≠0证明:如果g<sub>1</sub>(x)g<sub>2</sub>(x) | f<sub>1</sub>(x)f<sub>2</sub>(x), f<sub>1</sub>(x)|g<sub>1
-
设函数f在点x=1处二阶可导,证明:若f'(1)=0,f"(1)=0,则在x=1处有
设函数f在点x=1处二阶可导,证明:若f'(1)=0,f"(1)=0,则在x=1处有<img src='https://img2.soutiyun.com/ask/2020-11-28/975441569605878.png' />
<img src='https://img2.soutiyun.com/ask/2020-11-28/97544157767434.png' />
-
设f(x)=d(x)f<sub>1</sub>(x),g(x)=d(x)g<sub>1</sub>(x)证明:若(f(x),g(x))=d(x)且f(x)和g(x)不全为零,则(f<sub>1</sub>(x),g<sub>1</sub>(x))=1;反之,若(f<sub>1</sub>(x),g<sub>1</sub>(x))=1,则d(x)是f(x)与g(x)的一个最大公因式。
-
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).
-
设函数f(x)在[01]上二阶可导,且f"(x)≤0,x∈[0,1],证明:
设函数f(x)在[01]上二阶可导,且f"(x)≤0,x∈[0,1],证明:
<img src='https://img2.soutiyun.com/ask/2020-12-16/976976979900419.png' />
-
设f(x),g<sub>1</sub>(x),g<sub>2</sub>(x)∈C[x],证明:R(f,g<sub>1</sub>g<sub>2</sub>)=R(f,g<sub>1</sub>)R(f,g<sub>2</sub>)。
-
设f(x)=1/(a-x),证明:而且
设f(x)=1/(a-x),证明:<img src='https://img2.soutiyun.com/ask/2020-11-27/975320290099449.jpg' />
而且
<img src='https://img2.soutiyun.com/ask/2020-11-27/975320308867523.jpg' />
-
设f(x)为连续函数,又,证明: (1)若f(x)为奇函数,则F(x)为偶函数.(2) 若f(x)为偶函数,则F(x)为
设f(x)为连续函数,又<img src='https://img2.soutiyun.com/ask/2020-12-20/977330361227981.png' />,
证明: (1)若f(x)为奇函数,则F(x)为偶函数.
(2) 若f(x)为偶函数,则F(x)为奇函数.
-
设周期函数f(x)的周期为2π.证明:(1)如果f(x-π)=-f(x),则f(x)的傅里叶系数a<sub>0</sub>=0,a<sub>2k</sub>=0,b
设周期函数f(x)的周期为2π.证明:
(1)如果f(x-π)=-f(x),则f(x)的傅里叶系数a<sub>0</sub>=0,a<sub>2k</sub>=0,b<sub>2k</sub>=0(k=1,2,…);
(2)如果f(x-n)=f(x),则f(x)的傅里叶系数a<sub>2k</sub><sub>+1</sub>=0,b<sub>2k</sub><sub>+1</sub>=0(k=0,1,2,…).