Contact us
Choose a category below so we can get back to you as quickly as possible.
log對數函數值域為R的充要條件是那個括弧裏的函數可以取到所有正數(參照函數影像) 2^x-a+2可以看出是增函數(參照影像)所以只要他的最小值小於等於0他就可以取到所有正數 又因為2^x的最小值無限接近0(參照影像)所以整個式子最小值無限接近-a+2 所以只要-a+2小於等於0即a大於等於2即可
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.