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            • 1.

              用数学归纳法证明命题“当\(n\)是正奇数时,\({{x}^{n}}+{{y}^{n}}\)能被\(x+y\)整除”,在第二步的证明时,正确的证法是

              A.假设\(n=k(k\in {{N}^{*}})\),证明\(n=k+1\)时命题也成立

              B.假设\(n=k(k\)是正奇数\()\),证明\(n=k+1\)时命题也成立

              C.假设\(n=k(k\)是正奇数\()\),证明\(n=k+2\)时命题也成立

              D.假设\(n=2k+1(k\in N)\),证明\(n=k+1\)时命题也成立
            • 2.

              用数学归纳法证明等式:\((n+1)(n+2)…(n+n)=2^{n}·1·3·…·(2n-1)\),从\(k\)到\(k+1\),左边需要增乘的代数式为\((\)  \()\)

              A.\(2k+1\)     
              B.\(2(2k+1)\)      
              C.\( \dfrac{2k+1}{k+1}\)
              D.\( \dfrac{2k+3}{k+1}\)
            • 3.

              用数学归纳法证明不等式:\(\dfrac{1}{n+1}+ \dfrac{1}{n+2}+···+ \dfrac{1}{2n} > \dfrac{13}{24} \) \((n > 1,n∈{N}^{*} )\),在证明\(n=k+1\)这一步时,需要证明的不等式是(    )

              A.\(\dfrac{1}{k+1}+ \dfrac{1}{k+2}+···+ \dfrac{1}{2k} > \dfrac{13}{24} \)       

              B.\(\dfrac{1}{k+1}+ \dfrac{1}{k+3}+···+ \dfrac{1}{2k}+ \dfrac{1}{2k+1} > \dfrac{13}{24} \)

              C.\(\dfrac{1}{k+2}+ \dfrac{1}{k+3}+···+ \dfrac{1}{2k}+ \dfrac{1}{2k+1} > \dfrac{13}{24} \)

              D.\(\dfrac{1}{k+2}+ \dfrac{1}{k+3}+···+ \dfrac{1}{2k}+ \dfrac{1}{2k+1}+ \dfrac{1}{2k+2} > \dfrac{13}{24} \)
            • 4.
              已知数列\(\{{{a}_{n}}\}\)前\(n\)项和\({{S}_{n}}\)满足\({{s}_{n}}=2n-{{a}_{n}}\)。

              \((1)\)计算\({{a}_{1}}\)、\({{a}_{2}}\)、\({{a}_{3}}\)、\({{a}_{4}}\);

              \((2)\)由\((1)\)猜想数列\(\{{{a}_{n}}\}\)的通项公式,并用数学归纳法证明你的猜想。

            • 5.
              在各项为正的数列\(\{a_{n}\}\)中,数列的前\(n\)项和\(S_{n}\)满足\(S_{n}= \dfrac {1}{2}(a_{n}+ \dfrac {1}{a_{n}})\),
              \((1)\)求\(a_{1}\),\(a_{2}\),\(a_{3}\);
              \((2)\)由\((1)\)猜想数列\(\{a_{n}\}\)的通项公式,并用数学归纳法证明你的猜想.
            • 6.

              用数学归纳法证明\(\left(n+1\right)\left(n+2\right)···\left(n+n\right)={2}^{n}·1·3·...·\left(2n-1\right) \),从\(k\)到\(k+1\),左边需增乘的式子为(    )

              A.\(2k+1\) 
              B.\(2(2k+1)\) 
              C.\( \dfrac{2k+1}{k+1} \)
              D.\( \dfrac{2k+3}{k+1} \)
            • 7.

              已知\(f\left( n \right)={{1}^{2}}+{{2}^{2}}+{{3}^{2}}+\cdots +{{\left( 2n \right)}^{2}}\),则\(f\left( k+1 \right)\)与\(f\left( k \right)\)的关系是

              A.\(f\left( k+1 \right)=f\left( k \right)+{{\left( 2k+1 \right)}^{2}}+{{\left( 2k+2 \right)}^{2}}\)
              B.\(f\left( k+1 \right)=f\left( k \right)+{{\left( k+1 \right)}^{2}}\)          
              C.\(f\left( k+1 \right)=f\left( k \right)+{{\left( 2k+2 \right)}^{2}}\)
              D.\(f\left( k+1 \right)=f\left( k \right)+{{\left( 2k+1 \right)}^{2}}\)
            • 8.

              用数学归纳法证明不等式\( \dfrac{1}{n+1} + \dfrac{1}{n+2} +…+ \dfrac{1}{n+n\;} > \dfrac{1}{2} (n > 1,n∈N^{*})\)的过程中,从\(n=k\)到\(n=k+1\)时左边需增加的代数式是(    )

              A.\( \dfrac{1}{2k+2} \)
              B.\( \dfrac{1}{2k+1} - \dfrac{1}{2k+2} \)
              C.\( \dfrac{1}{2k+1} + \dfrac{1}{2k+2} \)
              D.\( \dfrac{1}{2k+1} \)
            • 9.

              利用数学归纳法证明不等式\(1+ \dfrac{1}{2} + \dfrac{1}{3} +… \dfrac{1}{{2}^{n}-1} < \)\(f\)\((\)\(n\)\() (\)\(n\)\(\geqslant 2\),\(n\)\(∈N^{*})\)的过程中,由\(n\)\(=\)\(k\)变到\(n\)\(=\)\(k\)\(+1\)时,左边增加了(    )

              A.\(1\)项         
              B.\(k\)
              C.\(2\) \({\,\!}^{k}\)\({\,\!}^{-1}\)项       
              D.\(2\) \({\,\!}^{k}\)
            • 10. 用数学归纳法证明\(1^{2}+2^{2}+3^{2}+…+n^{2}= \dfrac {n(n+1)(2n+1)}{6}\),\((n∈N^{*})\)
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