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Let $f(x) = {3}{x}$. We are told that $F(x) = ln(x^3) + 8$ is an anti-derivative. a. Verify that $f(x)$ is a derivative of $F(x)$. $F'(x) = $ b. Use the fundamental theorem of calculus to evaluate $ _1^{24} f(x)dx$. $ _1^{24} f(x)dx = $ c. Approximate $ _1^{24} f(x)dx$, using midpoint Riemann sums and 200 intervals. $ _1^{24} f(x)dx $See answer

Daftar Isi

Let f x 3x We are told that F x ln x3 8 is an anti derivative a Verify that f x is a derivative of F x F x b Use the fundamental theorem of calculus to evaluate 124 f x dx 124 f x dx c Approximate 124…

Question

Let $f(x) = \frac{3}{x}$. We are told that $F(x) = ln(x^3) + 8$ is an anti-derivative. a. Verify that $f(x)$ is a derivative of $F(x)$. $F'(x) = $ b. Use the fundamental theorem of calculus to evaluate $\int_1^{24} f(x)dx$. $\int_1^{24} f(x)dx = $ c. Approximate $\int_1^{24} f(x)dx$, using midpoint Riemann sums and 200 intervals. $\int_1^{24} f(x)dx \approx $

Basic Answer

Step 1: Verify F'(x) = f(x)

We need to find the derivative of F(x) = ln(x³) + 8. We can use the chain rule and the derivative of the natural logarithm.

The derivative of ln(u) is (1/u) * du/dx. In this case, u = x³.

F'(x) = (1/x³) * 3x² + 0 = 3/x = f(x)

Therefore, f(x) is indeed the derivative of F(x).

Step 2: Evaluate the definite integral using the Fundamental Theorem of Calculus

The Fundamental Theorem of Calculus states that ∫[a,b] f(x)dx = F(b) – F(a), where F(x) is an antiderivative of f(x).

We have F(x) = ln(x³) + 8 and we want to evaluate ∫[1,24] (3/x) dx.

F(24) = ln(24³) + 8
F(1) = ln(1³) + 8 = 8

∫[1,24] (3/x) dx = F(24) – F(1) = ln(24³) + 8 – 8 = ln(24³) = 3ln(24)

Step 3: Approximate the definite integral using midpoint Riemann sums

To approximate the integral using midpoint Riemann sums with 200 intervals, we follow these steps:

  1. Interval width: Δx = (24 – 1) / 200 = 0.115

  2. Midpoints: The midpoints of the intervals are xáµ¢ = 1 + (i – 0.5)Δx, where i = 1, 2, …, 200.

  3. Riemann sum: The midpoint Riemann sum is given by:

    ∑[i=1 to 200] f(xáµ¢)Δx = Δx * ∑[i=1 to 200] (3/xáµ¢)

    This sum is best calculated using a computer program or calculator. The result will be an approximation of 3ln(24).

Final Answer

a. F'(x) = 3/x
b. ∫[1,24] f(x)dx = 3ln(24) ≈ 8.294
c. ∫[1,24] f(x)dx ≈ 8.294 (This requires numerical computation; the exact value will depend on the precision of the calculation).