a function f is continuous on the closed interval [0,9] and has values given in the comments. as well as the rest of the question

Question

the trapezoidal approximation for 0 to 9 f(t) dt found with 3 subintervals, indicated by the data in the table is 57. what is k?

table:

x 0 4 7 9

f(x) 3 k 9 11

Answer 1

Hi again, Jo.

It is really important to graph these and draw in the trapezoids to get the correct answer.

I know some teachers/professors have a formula they use, but until you understand the process, the formula is very confusing and only works for equally spaced intervals. So please see video so that I can show you on a graph.