Question

不求值,利用因式分解说明25的7次方+5的13次方能被30整除

Answer 1

25^7+5^13

=(5^2)^7+5^13

=5^14+5^13

=5*5^13+5^13

=(5+1)*5^13

=6*5^13

=30*5^12

故能被30整除