Contact us
Choose a category below so we can get back to you as quickly as possible.
要分情况討論, a等於1時,原式=1×n=n a不等於1時,原式=[1-a^(n+1)]/(1-a)
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.