2007×2007/2008-1002×(-1003/1004)=(2008-1)×2007/2008+(1004-2)×1003/1004=2008×2007/2008-1×2007/2008+1004×1003/1004-2×1003/1004=2007-2007/2008+1003-1003/502=3010-2007/2008-4012/2008=3010-6019/200...