Contact us
Choose a category below so we can get back to you as quickly as possible.
-199 2+(3-2)=3,是第二個數,(雙數),要加負號. 3+(4-3)=5,是第三個數,(單數),不加符號. . 以此推論:n+(n+1-n)(n代表第幾個數) 第100個數:100+(100+1-100)=199,(雙數),要加負號. =-199
We and our partners use cookies and other technologies to analyze traffic and optimize your experience. View more info and control your cookies settings at any time in our Cookies Policy.