1-2+3-4+5-6.+2002-2003 Simple operation

1-2+3-4+5-6.+2002-2003 Simple operation

The sign behind you is wrong. It is positive before odd number and negative before even number
1-2+3-4+5-6.-2002+2003
=(1-2)+(3-4)+(5-6)+.+(2011-2002)+2003
=-1-1-1-…… -1 + 2003 (half of 2002, 1001 - 1)
=-1001+2003
=1002

What is the value of (- 2) ^ 2003 + (- 2) ^ 2002?

(-2)^2003+(-2)^2002
=(-2)^2002×(-2+1)
=(-2)^2002×(-1)
=-2^2002

How much is 1.01 + 1.02 + 1.03 +. + 1.99 + 2
If the title, the best explanation

The method is simple
1.01+1.02+1.03+.+1.99+2
=（1.01+2）+（1.02+1.99）+.+（1.50+1.51）
=3.01×50
=150.5