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            • 1.

              \((1)\)在\(\triangle ABC\)中,已知\(a=x,b=2,B=60^{\circ}\),如果\(\triangle ABC\) 两组解,则\(x\)的取值范围是_________

              \((2).\)一凸\(n\)边形,各内角的度数成等差数列,公差是\({{10}^{\circ }}\),最小内角是\({{100}^{\circ }}\),则边数\(n=\)______________


              \((3).\)有一解三角形的题因纸张破损,有一条件不清,且具体如下:在\(\Delta ABC\)中,已知\(a=\sqrt{3}{{,}^{{}}}B={{45}^{\circ }}\),____________,求角\(A.\) 经推断破损处的条件为三角形一边的长度,且答案提示\(A=60^{\circ}\),试将条件补充完整.


              \((4).\)一个由若干行数字组成的数表,从第二行起每一行中的数字均等于其肩上的两个数之和,最后一行仅有一个数,第一行是前\(100\)个正整数按从小到大排成的行,则最后一行的数是_________\((\)可以用指数表示\()\)

            • 2.

              \(7\)月份,有一款新服装投入某市场销售,\(7\)月\(1\)日该款服装仅销售出\(3\)件,\(7\)月\(2\)日售出\(6\)件,\(7\)月\(3\)日售出\(9\)件,\(7\)月\(4\)日售出\(12\)件,以后每天售出的件数分别递增\(3\)件直到日销售量达到最大\((\)只有\(l\)天\()\)后,每天销售的件数开始下降,分别递减\(2\)件,到\(7\)月\(31\)日刚好售出\(3\)件.

                  \((1)\)问\(7\)月几号该款服装销售件数最多\(?\)其最大值是多少\(?\)

                  \((2)\)按规律,当该商场销售此服装达到\(200\)件时,社会上就开始流行,而日销售量连续下降并低于\(20\)件时,则不再流行,问该款服装在社会上流行几天\(?\)说明理由.

            • 3.

              在等差数列\(\left\{ {{a}_{n}} \right\}\)中,公差\(d=2,{{a}_{n}}=11,{{S}_{n}}=35\),则\({{a}_{1}}\)等于\((\)  \()\)

              A.\(5\)或\(7\)
              B.\(3\)或\(5\)
              C.\(7\)或\(-1\)
              D.\(3\)或\(-1\)
            • 4.
              已知在等差数列\(\{a_{n}\}\)中,\(a_{3}=5\),\(a_{1}+a_{19}=-18\)
              \((1)\)求公差\(d\)及通项\(a_{n}\)
              \((2)\)求数列 \(\{a_{n}\}\)的前\(n\)项和\(S_{n}\)及使得\(S_{n}\)的值取最大时\(n\)的值.
            • 5.
              已知数列\(\{a_{n}\}{中},a_{1}= \dfrac {1}{2},{点}(n,2a_{n+1}-a_{n})(n∈N^{*}){在直线}y=x{上}\),
              \((\)Ⅰ\()\)计算\(a_{2}\),\(a_{3}\),\(a_{4}\)的值;
              \((\)Ⅱ\()\)令\(b_{n}=a_{n+1}-a_{n}-1\),求证:数列\(\{b_{n}\}\)是等比数列;
              \((\)Ⅲ\()\)设\(S_{n}\)、\(T_{n}\)分别为数列\(\{a_{n}\}\)、\(\{b_{n}\}\)的前\(n\)项和,是否存在实数\(λ\),使得数列\(\{ \dfrac {S_{n}+λT_{n}}{n}\}\)为等差数列?若存在,试求出\(λ\)的值;若不存在,请说明理由.
            • 6.
              \(S_{n}\)为等差数列\(\{a_{n}\}\)的前\(n\)项和,已知\(a_{5}+a_{6}+a_{7}=15\),则\(S_{11}\)为\((\)  \()\)
              A.\(25\)
              B.\(30\)
              C.\(35\)
              D.\(55\)
            • 7.

              设数列\(\left\{ {{a}_{n}} \right\}\)满足\({{a}_{1}}+2{{a}_{2}}=2\),且对任意的\(n\in {{N}^{*}}\),点\({{P}_{n}}(n,{{a}_{n}})\)都有\(\overrightarrow{{{P}_{n}}{{P}_{n+1}}}=(1,2)\),则数列\(\left\{ {{a}_{n}} \right\}\)的前\(n\)项和为__________.

            • 8.

              已知等差数列\(\{a_{n}\}\)的前\(n\)项和为\(Sn\),等比数列\(\{b_{n}\}\)的前\(n\)项和为\(Tn\),\(a_{1}=-1\),\(b1=1\),\(a3+b2=2\).

              \((1)\)若\(a3+b2=5\),求\(\{b_{n}\}\)的通项公式;

              \((2)\) 若\(T=21\),求\(S_{1}\)

            • 9.

              填空题

              \((1)\triangle ABC\)中,\(A={{60}^{\circ }}\),\(b = 1\),\({S}_{∆ABC}= \sqrt{3} \),则\( \dfrac{a+b+c}{\sin A+\sin B+\sin C}= \)________ .

              \((2)\)在公差不为\(0\)的等差数列\(\left\{{{a}_{n}}\right\} \)中,\({a}_{1}+{a}_{3}=8 \),且\(a_{4}\)为\(a_{2}\)和\(a_{9}\)的等比中项,则\(a_{5}=\)_____.

              \((3)∆ABC \)三内角\(A\),\(B\),\(C\)的对边分别为\(a\),\(b\),\(c\),\( \sqrt{3}\sin A-a\cos B-2a=0 \),则\(∠B= \)_______.

              \((4)\)已知数列\(\left\{{{a}_{n}}\right\} \)中,\({{a}_{1}}=-60,{a}_{n+1}={a}_{n}+3 \),则\(\left|{a}_{1}\right|+\left|{a}_{2}\right|+\left|{a}_{3}\right|+……+\left|{a}_{30}\right|= \)___________.

            • 10.

              若存在常数\(k\left( k\in {{N}^{*}},k\geqslant 2 \right)\)\(q\)\(d\),使得无穷数列\(\left\{ {{a}_{n}} \right\}\)满足\({{a}_{n+1}}=\begin{cases} {{a}_{n}}+d,\dfrac{n}{k}\notin {{N}^{*}} \\ q{{a}_{n}},\dfrac{n}{k}\in {{N}^{*}} \\\end{cases}\)则称数列\(\left\{ {{a}_{n}} \right\}\)为“段比差数列”,其中常数\(k\)\(q\)\(d\)分别叫做段长、段比、段差\(.\)设数\(\left\{ {{b}_{n}} \right\}\)为“段比差数列”,它的首项、段长、段比、段差分别为\(1\)、\(3\)、\(q\)、\(3\).

                \((1)\)当\(q=0\)时,求\({{b}_{2014}}\),\({{b}_{2016}}\);

                \((2)\)当\(q=1\)时,设\(\left\{ {{b}_{n}} \right\}\)的前\(3n\)项和为\({{S}_{3n}}\),

                     \(①\)证明:\(\left\{ {{b}_{3n-1}} \right\}\)为等差数列;

                     \(②\)证明:\({{b}_{3n-2}}+{{b}_{3n}}=2{{b}_{3n-1}}\);

                     \(③\)若不等式\({{S}_{3n}}\leqslant \lambda \cdot {{3}^{n-1}}\)对\(n\in {{N}^{*}}\)恒成立,求实数\(\lambda \)的取值范围;

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