请用数学归纳法证明:
(n+1)^2+(n+2)^2+(n+3)^2+...+(2n)^2=n(2n+1)(7n+1)/6
数学归纳法 (n+1)^2+(n+2)^2+(n+3)^2+...+(2n)^2 急急急~ 在线等
=(14n^3+37n^2+24n+14n^2+37n+24)\/6 =(14n^3+51n^2+61n+24)\/6 将此结果减去(14n^3+9n^2+n)\/6得 (14n^3+51n^2+61n+24-14n^3+9n^2+n)\/6 =(42n^2+60n+24)\/6=7n^2+10n+4 当n=n+1时,与n=n时相比,原式增加了两项:(2n+1)^2+(2n+2)^2 =4n^2...
用数学归纳法证明:(n+1)^2+(n+2)^2+……(n+n)^2=n(2n+1)(7n+1)\/6
n^2+2n+1+n^2+4n+4+……+4n^2=(n+3)n^2+(1+n-1)n(n-1)+1+4+9+16+25+……+(n-1)^2 =(n+3)n^2+(n-1)n^2+1+4+9+16+25+……+(n-1)^2 =
用数学归纳法证明:(n+1)^2+(n+2)^2+……(n+n)^2=n(2n+1)(7n+1)\/6
n^2+2n+1+n^2+4n+4+……+4n^2=(n+3)n^2+(1+n-1)n(n-1)+1+4+9+16+25+……+(n-1)^2 =(n+3)n^2+(n-1)n^2+1+4+9+16+25+……+(n-1)^2 =
用数学归纳法证明:(n+1)(n+2)(n+3)+...+(n+n)=(2^n)*1*3*...(2n-1...
n=1时,n+1=2 (2^1)*1=2,等式成立。假设当n=k(k为自然数,且k>=1)时等式成立。即 (k+1)(k+2)...(k+k)=(2^k)*1*3*...*(2k-1)则当n=k+1时,(k+1+1)(k+1+2)...(k+1+k-1)(k+1+k)(k+1+k+1)=(k+2)(k+3)...(k+k)(2k+1)(2k+2)=(k+1)(...
用数学归纳法证明:(n+1)(n+2)(n+3)+...+(n+n)=(2^n)*1*3*...(2n-1...
则当n=k+1时,(k+2)(k+3)...(k+1+k-1)(k+1+k)(k+1+k+1)=(k+2)(k+3)...(k+k)(k+1+k)2(k+1)=(2^k)*1*3*...(2k-1)*2*(2k+1)=(2^k+1)*1*3*...(2k-1)(2k+1)所以:(n+1)(n+2)(n+3)...(n+n)=(2^n)*1*3*...(2n-1)好辛苦 给分...
用数学归纳法证明:(n+1)(n+2)…(n+n)=2 n ·1·3·…·(2n-1) 其中n...
思路分析:用数学归纳法证明一个与正整数有关的命题时 关键是第二步 要注意当n=k+1时 等式两边的式子与n=k时等式两边的式子的联系 增加了哪些项或减少了哪些项 问题就容易解决了.证明:(1)当n=1时 左边1+1=2 右...
用数学归纳法证明完全平方公式 (n+1)^2=n^2+2n+1?
数学归纳法就是分三步,1,验证对于n=1时成立 2,假设n=k时成立 3,验证n=k+1时成立 则对于所有n都成立.因此步骤如下:1,当n=1时,(1+1)^2=2^2=4,1^2+2*1+1=4,(1+1)^2=1^2+2*1+1,成立.2,假设n=k,则有(k+1)^2=k^2+2k+1 3,当n=k+1时,[(k+1)+1]^2=(k+2...
1^2+2^2+3^2+...+n^2=?的公式推导
解题过程如下:
用数学归纳法证明 (n+1)(n+2)…(n+n)=2^n·1·3·……·(2n-1)(n∈...
你好!当n=k时,左边=(k+1)(k+2)…(k+k)当n=k+1时,左边 = [(k+1)+1][(k+1)+2]…[(k+1)+(k-1)][(k+1)+k][(k+1)+(k+1)]= (k+2)(k+3)…(k+k)(2k+1)(k+1)*2 所以从n=k到n=k+1,左端需乘以 2(2k+1)...
用数学归纳法证明:(n+1)+(n+2)+…+(n+n)=n(3n+1)2(n∈...
证明:①n=1时,左边=2,右边=2,等式成立;②假设n=k时,结论成立,即:(k+1)+(k+2)+…+(k+k)= k(3k+1)2 则n=k+1时,等式左边=(k+2)+(k+3)+…+(k+k+1)+(k+1+k+1)= k(3k+1)2 +3k+2= (k+1)(3k+4)2 故n=k+1时,等式成立 由①②可知:(n+1)+(n+2)+…+(...