Question

tính nhanh 2 x 3 x 12 + 4 x 6 x 42 + 8 x 27 x 3

 

Answer 1

   2 x 3 x 12 + 4 x 6 x 42 + 8 x 27 x 3

= 2 x 12 x 3 + 4 x 6 x 42 + 8 x 3 x 27

= 24 x 3 + 24 x 42 + 24 x 27

= 24 x ( 3 + 42 + 27 )

= 24 x 72

= 1728

Answer 2

2x3x12+4x6x42+8x27x3

=2x3x4x3+4x2x3x42+4x2x27x3

=2x3x4x(3+42+27)

=24x72

=1728

Answer 3

  2 x 3 x 12 + 4 x 6 x 42 + 8 x 27 x 3

= 2 x 3 x 12 + 2 x 2 x 6 x 42 + 2 x 4 x 27 x 3

= 2 x 36 + 2 x 504 + 2 x 324

= 2 x ( 36 + 504 + 324 )

= 2 x 864 = 1728 .