Contact us
Choose a category below so we can get back to you as quickly as possible.
設X=x-1,則y=-1/2X^2+2 當X>0時,y隨著X增大遞增,此時X=x-1>0,即x>1 當X
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.