Question

Trapezoidal rule question?? Please help!

Answer 1

F(x) is continuous on the closed interval [1, 5] and goes through the following points:

x = 1, 2, 3, 4, 5
f(x) = 1.62, 4.15, 7.50, 9.00, 12.13

Use the trapezoidal rule, with n = 4 to approximate the area under the curve from x = 1 to x = 5

Answer 2

so the formula for a trapezoid is 1/2(b1+b2) if I'm not mistaken so that should mean that we have 1/2(1.62+2(4.15)+2(7.5)+2(9)+12.13)

Answer 3

Oh so you don't multiply the first 1.62 by 2?

Answer 4

I guess that is what I was doing wrong.

Answer 5

Thanks!

Answer 6

if you draw out what the trapezoidal rule looks like you see that you need to use every length twice besides the first and the last since they only touch one trapezoid