Answer:
The number of watches must he repair to have the lowest cost is 54.
Step-by-step explanation:
The cost of operating Bob's shop is given by
Differentiate the given function with respect to x.
... (1)
Equate C'(x) equal to 0, to find the critical point.
Divide both sides by 4.
Differentiate C'(x) with respect to x.
C''(x)>0, it means the cost of operating is minimum at x=54.
Therefore the number of watches must he repair to have the lowest cost is 54.
Answer:
His acceleration is meters per seconds²
Step-by-step explanation:
Acceleration is the rate of change of the speed
The formula of acceleration is , where
∵ Jim goes from 70 meters/minute (beginning speed) to
106 meters/minute (final speed) in 9 seconds
∴ His initial speed = 70 meters/minute
- Change it the meter per second
∵ 1 minute = 60 seconds
∴ meters/second
∴ =
meters/second
∵ His final speed = 106 meters/minute
- Change it the meter per second
∴ meters/second
∴ =
meters/second
∵ The time of the change of his speed is 9 seconds
∴ t = 9
∵ The formula of acceleration is
- Substitute the values of t, and
in the formula above
∴
∴ His acceleration is meters per seconds²