问题
解答题
199-198+197-196+195-194+…+5-4+3-2+1.
答案
199-198+197-196+195-194+…+5-4+3-2+1,
=(199-198)+(197-196)+…+(5-4)+(3-2)+1,
=1+1+…+1,
=100.
199-198+197-196+195-194+…+5-4+3-2+1.
199-198+197-196+195-194+…+5-4+3-2+1,
=(199-198)+(197-196)+…+(5-4)+(3-2)+1,
=1+1+…+1,
=100.