Answer:
21 ÷ 1.4
Step-by-step explanation:
Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour.
The temperature had fallen 21 degrees, so it passed
hours after she had first checked the thermometer.
She had first checked the temperature at 3 p.m.
Answer:
f'(x) > 0 on and f'(x)<0 on
Step-by-step explanation:
1) To find and interval where any given function is increasing, the first derivative of its function must be greater than zero:
To find its decreasing interval :
2) Then let's find the critical point of this function:
2.2 Solving for x this equation, this will lead us to one critical point since x' is not defined for Real set, and x''≈0.37 for e≈2.72
3) Finally, check it out the critical point, i.e. f'(x) >0 and below f'(x)<0.
