1x7x9x4x9-7x4x556=?

1x7x9x4x9-7x4x556=?


1x7x9x4x9-7x4x556

=(7x9x4x9)-(7x4x556)----------乘1可以省去

=[(9*9)*(7*4)]-[(7*4)*(556)]-----列成較易相乘的形式

=81*28-28*556

=2268-15568

=-13300------------------if a-b,b>a,則答案為負數

1x7x9x4x9-7x4x556=?
=7x9x4x9-28x556
=63x4x9-15568
=252x9-15568
=2268-15568
=-13300

1x7x9x4x9-7x4x556
=2268-15668
=-13300

-13300

1x7x9x4x9-7x4x556
=-13300

如果係1x7x9x4x9-7x4x556就係 = 5028464
如果係1x7x9x4x9x4x556-7就係= 140105

1x7x9x4x9-7x4x556
=2268-15568
=-13300(負數)

= 5028464

=-13300

-14992