Question

1-2+3-4+5-6+7-8+9.+2007-2008=?

Answer 1

1-2+3-4+5-6+7-8+9.+2007-2008

=(1-2)+(3-4)+...+(2007-2008)

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

=-1×2008÷2

=-1004;

很高兴为您解答,skyhunter002为您答疑解惑

如果本题有什么不明白可以追问,