优优班--学霸训练营 > 知识点挑题
全部资源
          排序:
          最新 浏览

          50条信息

            • 1.

              \((1)\)已知\(-1,{{a}_{1}},{{a}_{2}},{{a}_{3}},-9\)五个实数成等差数列,\(-1\),\(b1\),\(b2\),\(b3\),\(-9\)五个实数成等比数列,则\((a1-a3)/b2\)等于_______ .

              \((2)\dfrac{\sin 160{}^\circ }{\sin 110{}^\circ }-\tan 320^{\circ}+\sqrt{3}\tan 20^{\circ}\tan 40^{\circ}=\)______.

              \((3)\)已知集合\(A=\{\left. x \right|{{x}^{2}}-16 < 0\}\),\(B=\{x\left| {{x}^{2}}-4x+3 > 0 \right.\}\),则\(A∩B=\)_________.

              \((4)\)如图,测量河对岸的塔高\(AB\)时,可以选与塔底在同一水平面内的两个测点\(C\)与\(D\),测得,测得\(∠BCD=75^{\circ}\),\(CD=60\),\(∠BDC=60^{\circ}\),并在点\(C\)测得塔顶\(A\)的仰角为\(60^{\circ}\),则塔高\(AB=\)________\(m\).

            • 2.

              已知数列\(\{a_{n}\}\)满足:\(a_{1}=1\),\(a_{2}=2\),\({{a}_{n+2}}=(1+{{\cos }^{2}}\dfrac{n\pi }{2}){{a}_{n}}+{{\sin }^{2}}\dfrac{n\pi }{2}\),\(n=1\),\(2\),\(3\),\(…\)

              \((\)Ⅰ\()①\)求\(a_{3}\),\(a_{4}\),\(a_{5}\),\(a_{6}\);

              \(②\)证明数列\(a_{1}\),\(a_{3}\),\(a_{5}\),\(a_{7}\),\(…\),\(a_{2k-1}\),\(…(k∈N^{*})\)成等差数列

              \((\)Ⅱ\()\)设\({{b}_{n}}=\dfrac{1}{{{a}_{2n-1}}\cdot \sqrt{{{a}_{2n+1}}}+{{a}_{2n+1}}\cdot \sqrt{{{a}_{2n-1}}}}\),若\(T_{n}=b_{1}+b_{2}+…+b_{n}\),求\(T_{n}\)

            • 3.

              设\({{S}_{n}}\)为数列\(\left\{ {{a}_{n}} \right\}\)的前\(n\)项和,已知\({{a}_{1}}=2\) ,对任意\(p,q\in N^{*}\),都有\({{a}_{p+q}}={{a}_{p}}+{{a}_{q}}\),则\(f\left( n \right)=\dfrac{{{S}_{n}}+60}{n+1}(n\in N^{*})\)的最小值为         \(.\) 

            • 4.

              我国古代数学名著\(《\)张邱健算经\(》\)有“分钱问题”如下:“今有人与钱,初一人与三钱,次一人与四钱,次一人与五钱,以次与之,转多一钱,与讫,还数聚与均分之,人得一百钱,问人几何?”意思是:将钱分给若干人,第一人给\(3\)钱,第二人给\(4\)钱,第三人给\(5\)钱,以此类推,每人比前一人多给\(1\)钱,分完后,再把钱收回平均分给各人,结果每人分得\(100\)钱,问有多少人?则分钱问题中的人数为\(\_\)    \(\_\)

            • 5.

              若集合\(G=\{3,4\}\),数列\(\{a_{n}\}\),\(a_{1}=1\),\(a_{1}+a_{2}+…+a_{n}=T_{n}\),已知\(m∈G\),当\(n > m\)时,\(\dfrac{{{T}_{n+m}}+{{T}_{n-m}}}{{{T}_{n}}+{{T}_{m}}}=2\)恒成立,则数列\(\{a_{n})\)的通项公式\(a_{n}=(\)   \()\)

              A.\(3^{n}-2\)
              B.\(2^{n}-1\)
              C.\(3n-2\)
              D.\(2n-1\)
            • 6. 已知等差数列\(\{{{a}_{n}}\}\)满足\({{a}_{1}}=1,{{a}_{2}}=2\),\(2{a}_{n-1} < {a}_{n-1}+{a}_{n+1} < 2{a}_{n+1}(n∈N,n\geqslant 2) \).
              \((\)Ⅰ\()\)求数列\(\{{{a}_{n}}\}\)的通项公式;\((\)Ⅱ\()\)将数列\(\{{{a}_{n}}\}\)中的所有项依次按如图所示的规律循环地排成如下三角形数表:
              第\(1\)行    \({{a}_{1}}\) 第\(2\)行   \({{a}_{2}}\)    \({{a}_{3}}\) 第\(3\)行 \({{a}_{4}}\)   \({{a}_{5}}\)   \({{a}_{6}}\) 第\(4\)行 \({{a}_{7}}\)   \({{a}_{8}}\)   \({{a}_{9}}\)   \({{a}_{10}}\)


              \(……\)
              依次计算各个三角形数表内各行中的各数之和设由这些和按原来行的前后顺序构成的数列为\(\{{{b}_{n}}\}\),求\({{b}_{5}}+{{b}_{100}}\)的值; \((\)Ⅲ\()\)令\({{c}_{n}}=2+b{{a}_{n}}+b\cdot {{2}^{{{a}_{n}}-1}}\) \((b\)为大于等于\(3\)的正整数\()\),问数列\(\{{{c}_{n}}\}\)中是否存在连续三项成等比数列?若存在,求出所有成等比数列的连续三项;若不存在,请说明理由.
            • 7.

              已知各项均为正数的等比数列\(\{a_{n}\}\)满\(-{{a}_{3}},{{a}_{2}},{{a}_{4}}\)成等差数列

              \((1)\)若\({{a}_{1}}=1\),求\(\{a_{n}\}\)的前项和\({{S}_{n}};\)

              \((2)\)若\({{b}_{n}}={{\log }_{2}}{{a}_{2n+1}}\),且数列\(\left\{ {{b}_{n}} \right\}\)的前\(n\)项和\({{T}_{n}}={{n}^{2}}+3n\),求\({{a}_{1}}\)

            • 8.

              已知函数\(f\left(x\right) \)满足\(f\left(n+1\right)=f\left(n\right)+n+1\left(n∈{N}_{+}\right) \) ,且\(f\left(1\right)=1 \) ,则\(f\left(100\right)= \)    

            • 9.

              \((1)\tan \,{{15}^{0}}=\)          \(.(\)以最简式作答\()\)

              \((2)\)如图,设\(A\)\(B\)两点在河的两岸,一测量者在\(A\)所在的同侧河岸边选定一点\(C\),测出\(AC\)的距离为\(50m\),\(∠\)\(ACB\)\(=45^{\circ}\),\(∠\)\(CAB\)\(=105^{\circ}\),计算出\(A\)\(B\)两点的距离为         \(m.\) 

              \((3)\)关于\(x\)的方程\({{x}^{2}}+2(a-1)x+2a+6=0\)有两个正根,则实数\(a\)的取值范围为         

              \((4)\)数列\(\{{{a}_{n}}\}\)的前\(n\)项和为\({{S}_{n}}\),且\({{a}_{1}}=6,{{a}_{n}}=2{{a}_{n-1}}+{{2}^{n}}(n\in {{N}^{*}},n\geqslant 2)\),若存在实数\(\lambda \),使得数列\(\{\dfrac{{{S}_{n}}+\lambda }{{{2}^{n+1}}}\}\)是等差数列,则\(\lambda =\)                .

            • 10.

              若\(\left\{ {{a}_{n}} \right\}\)为等差数列,则下列数列仍为等差数列的有\((\)     \()\)

              \((1)\{a_{n}+1\}\),\((2)\{a_{n}^{2}\}\),\((3)\{a_{n+1}-a_{n}\}\),\((4)\{2a_{n}\}\),\((5)\{a_{n}+n\}\)


              A.\(1\)个      
              B.\(2\)个      
              C.\(3\)个      
              D.\(4\)个
            0/40

            进入组卷