Final answer:
To find the average rate of change of the function f(x) = sec(x) + csc(x) over the interval [π/4 , 3π/8], we use the formula: Average Rate of Change = (f(b) - f(a))/(b - a).
Step-by-step explanation:
The average rate of change of a function f over an interval [a, b] is given by the formula:
Average Rate of Change = (f(b) - f(a))/(b - a).
In this case, f(x) = sec(x) + csc(x). To find the average rate of change over the interval [π/4 , 3π/8], we substitute π/4 for a and 3π/8 for b in the formula and calculate:
Average Rate of Change = (f(3π/8) - f(π/4))/(3π/8 - π/4).
By simplifying the expression, we find the average rate of change of f over the given interval. The average rate of change of the function f(x) = sec x + csc x over the interval [π /4 , 3π /8] is calculated using the formula ∆f / ∆x, which is the difference in the function values divided by the difference in the x-values. In mathematical terms, it is (f(3π /8) - f(π /4)) / (3π /8 - π /4). Hence, the correct answer is C.