我要怎麼解釋25的平方就是5乘5=25之後 在(2加1)乘2會=6 然後我就知道答案是625?
回答 (2)
2015-09-15 2:58 pm
Sol
p=10*a+5
p^2=(10a+5)^2
=100a^2+100a+25
=100(a^2+a)+25
=100a(a+1)+25
So
25^2
=100*2*3+25
p=10*a+5
p^2=(10a+5)^2
=100a^2+100a+25
=100(a^2+a)+25
=100a(a+1)+25
So
25^2
=100*2*3+25
2015-09-15 4:32 pm
收錄日期: 2021-04-21 14:11:51
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20150915054916AAfoRf6