Question

1-2+3-4+5-6+7-8+....+12343-12344+12345

Answer 1

1-2+3-4+5-6+7-8+....+12343-12344+12345

=(1-2)+(3-4)+(5-6)+(7-8)+....+(12343-12344)+12345

=(-1)+(-1)+(-1)+(-1)+....+(-1)+12345

=(-1)*6172+12345

=-6172+12345

=6173 nha bạn !!!!!!!!!!!!!!!!!!!!!!!!!

Answer 2

\(\left(1-2\right)+\left(3-4\right)+...+\left(12343-12344\right)+12345\)

\(\left(-1\right)-1-1-...-1+12345\) có 6172 số -1

-6172+12345=6173