15^2-25=200(2=1*2);25^2-25=600(6=2*3);35^2-25=1200(12=3*4).....用字母a表示规律,并给出证明

2024-11-29 00:18:24
推荐回答(3个)
回答1:

规律(10a+5)^2-25=a*(a+1)*100 a=1,2,3……
解答:左边=(10a+5)^2-25=100a^2+100a+25-25=100a^2+100a=100*a*(a+1)=右边

回答2:

(10a+5)^2-25=100a*(a+1)
证明
(10a+5)^2-25
=(100a^2+100a+25)-25
=100a^2+100a
=100a(a+1)

回答3:

(10a+5)^2-25=100*a*(a+1)
证明
(10a+5)^2-25=(100a^2+100a+25)-25=100a^2+100a=100a(a+1)