Question

A company has tow electric motors consume varying amounts of power. The power consumed by each motor is a function of the time (t in minutes) for which it runs. The cost of power (in $) to run one motor is given by the function Ca(t)=t^2-2t+5. The cost of running the second motor is given by Cb(t)=3t+2. Which gives the total cost of running both motors?

C(t)=3t^3-6t^2+15t
C(t)=2t^2-4t+10
C(t)=t^2+t+7
C(t)=3t^3+6t^2-15t

Answer 1

C(t)=t^2+t+7

To get this answer you must add the two equation together, and add together the like terms (Ex. 3t-2t and 5+2)

Answer 2

Option (c) is correct.

The total cost of running both motors is
`t^2+t+7`

Explanation:

Given : The cost of power (in $) to run one motor is given by the function
`C_a(t)=t^2-2t+5` and The cost of running the second motor is given by
`C_b(t)=3t+2`

We have to find the total cost of running both motors.

Since we are given the cost to run each motors so, total cost will be the sum of running both motors.

Let C(t) be the total cost of running both motors.

`C(t)=C_a(t)+C_b(t)`

Substitute,

`C_a(t)=t^2-2t+5`

and
`C_b(t)=3t+2`

We get,

`C(t)=t^2-2t+5+3t+2`

Simplify, we get,

`C(t)=t^2+t+7`

Thus, The total cost of running both motors is
`t^2+t+7`