Question

若a=5^0.2，b=0.5^0.2，c=0.5²，則（　�。�

A．a＞b＞c

B．b＞a＞c

C．c＞a＞b

D．b＞c＞a

Answer 1

∵函數y=0.5^x為R上單調減函數，且0＜0.2＜2
∴1=0.5⁰＞0.5^0.2＞0.5²
∵函數y=5^x為R上單調增函數，且0＜0.2
∴5^0.2＞5⁰=1
∴a＞b＞c
故選A