Find the exact value of 2012-2002+1992-1982 +...+ 32 - 22 + 12 - 2
We can call two adjacent terms a pair. For example, 2012 and -2002 is a pair and 32, -22 is also a pair. And the sum of the two values in each pair is 10. There are 101 pairs in totally and the sum of all the pairs should be\(101\cdot10=1010.\)
