Tính nhanh: a) 136 x 2 + 136 x 7 + 136 ............................................................... ................................................................ ................................................................ ............................................................... b) 3465 x 9 x (72 - 8 x 9) ................................................................ ................................................................ ........................................................
a) = 136 x 2 + 136 x 7 + 136 x 1
= 136 x ( 2 + 7 + 1 )
= 136 x 10
= 1360
b) = 3465 x 9 x 0
= 0
a) = 136 x 2 + 136 x 7 + 136 x 1
= 136 x ( 2 + 7 + 1 )
= 136 x 10
= 1360
b) = 3465 x 9 x 0
= 0