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用数学归纳法证明1+2×2+3x3+……+n×n=n×(n+1)x(2n+1)÷6

题目详情
用数学归纳法证明1+2×2+3x3+……+n×n=n×(n+1)x(2n+1)÷6
▼优质解答
答案和解析
n=1LS=1=RSp(1) is trueAssume p(k) is trueie1^2+2^2+...+k^2 = k(k+1)(2k+1)/6for n=k+1LS=1^2+2^2+...+k^2+(k+1)^2 = k(k+1)(2k+1)/6 +(k+1)^2 = [(k+1)/6] [k(2k+1) + 6(k+1) ] = [(k+1)/6] (2k^2+7k+6...