Question

简算 137×73-183×17-83×83

Answer 1

183×17=100*17+83*17

183*17+83*83

=100*17+83*17+83*83

=17*100+83*100

=100*100

=10000

137*73

=127*73+10*73

=（100+27）*（100-27）+730

=100*100-27*27+730

原式=100*100-27*27+730-100*100

=730-27*27

=730-729

=1