Question

Tinh mot cach hop li nhat :

a) 512.(2-128) - 128.(-512)

b) 2155-(174 + 2155) + ( -68 + 174)

Answer 1

a, =512 . -126 - 128 . -512

= -512 . 126 - 128 . -512

= -512.[126 - 128]

= -512.-2

=1024

b, =2155 - 174 - 2155 + 106

=2155-2155 - 174 +106

=0 - 174 +106

=-68

Answer 2

a) \(=512\cdot\left(2-128\right)+128\cdot512 \)

\(=512\cdot\left(2-128+128\right)\)

\(=512\cdot2=1024\)

Answer 3

2155 - (174 + 2155) + ( -68 + 174)

= ( 2155 - 2155 ) + ( 174 - 174 ) + ( -68 )

=          0           +         0         + ( -68 )

=                       -68