已知某物体的温度θ(单位:摄氏度)随时间t(单位:分钟)的变化规律是:θ=m•2
t+2
1-t(t≥0,并且m>0).
(1)如果m=2,求经过多少时间,物体的温度为5摄氏度;
(2)若物体的温度总不低于2摄氏度,求m的取值范围.
考点分析:
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