Question

Urgent please help with finding rate of change

Answer 1

When working with functions (of all types), the average rate of change is expressed using function notation:

`(f(b)-f(a))/(b-a).`

For the interval from x=7 to x=8,

1. find f(7) and f(8):

• 
  `f(7)=729\cdot 3=2187;`
• 
  `f(8)=2187\cdot 3=6561;`

2. use given formula:

`(f(8)-f(7))/(8-7)=(6561-2187)/(8-7)=4374.`

Answer: the average rate of change for the interval from x=7 to x=8 is 4374.