Question

Tính giá trị biểu thức:

B = 1 + 2 - 3 - 4 + 5 + 6 - ... - 303 - 304 + 305 + 306

Answer 1

B = 1 + 2 - 3 - 4 + 5 + 6 - ... - 303 - 304 + 305 + 306

= 1 + ( 2 - 3 - 4 + 5 ) + .... + ( 302 - 303 - 304 - 305 ) + 306

= 1 + 0 + .... + 0 + 306 = 307

vậy B = 307 

Answer 2

1+2-3-4+5+6-...-303-304+305+306

=1+2-2+3-3+4-4+5-5+6-6+...+303-303+304-304+305-305+306

=1+306

=307

Answer 3

B = 1 + 2 - 3 - 4 + 5 + 6 - ... - 303 - 304 + 305 + 306

 = 1 + ( 2 - 3 - 4 + 5 ) +...+ ( 302 - 303 - 305 ) + 306

= 1 + 0 + ... + 0 + 306 = 307

\(\Rightarrow\)B = 307