Final answer:
The value of R8 for the function f(x) = 9-x over the interval [3,5] is 4.
Step-by-step explanation:
To find the value of R8 for the function f(x) = 9-x over the interval [3,5], we need to substitute the x-values of 3 and 5 into the function and solve for R8. Let's start by substituting 3 into the function:
f(3) = 9 - 3 = 6
Next, let's substitute 5 into the function:
f(5) = 9 - 5 = 4
Therefore, the value of R8 for the function f(x) = 9-x over the interval [3,5] is 4.