证明:1^2 3^2 5^2 (2k-1)^2=1/3k(4k^2-1)
问题描述:
证明:1^2 3^2 5^2 (2k-1)^2=1/3k(4k^2-1)
答
归纳法:(1)当n=1时 左边等于1右边等于1/3*1*(4*1^2-1)=1(2)假设当k=n时 等式成立 则1^2+3^2+5^2+(2k-1)^2=1/3k(4k^2-1)则当n=k+1时(2k+1)^2+1/3*k*(4k^2-1) =(2k+1)^2+1/3*k(2k+1)(2k-1)=(2k+1)(5/3k+1+2/3k^)=1/3...