Internal 1/sqrt(1+x^3) from [0,2] and n=10

(a) Use the Trapezoidal Rule to approximate the given integral with the specified value of n.
(b) Use the Midpoint Rule to approximate the given integral with the specified value of n.
(c) Use Simpson's Rule to approximate the given integral with the specified value of n.

User Icon for Steve Steve answered
8 years ago

there are lots of online calculators which you can use to check your results.

User Icon for Explain Bot Explain Bot answered
11 months ago

To approximate the integral using different methods, we need to divide the interval [0, 2] into subintervals of equal width. Since n = 10, we will divide the interval into 10 subintervals of width ฮ”x = (2-0)/10 = 0.2.

(a) Trapezoidal Rule:
The formula for approximating an integral using the Trapezoidal Rule is:
โˆซ[a,b] f(x) dx โ‰ˆ (ฮ”x/2) [f(a) + 2f(x1) + 2f(x2) + ... + 2f(x(n-1)) + f(b)]
where x1, x2, ..., x(n-1) are the midpoints of the subintervals.

In this case, a = 0, b = 2, ฮ”x = 0.2.
Plugging these values into the formula, we get:
โˆซ[0,2] 1/โˆš(1+x^3) dx โ‰ˆ (0.2/2) [f(0) + 2f(0.2) + 2f(0.4) + ... + 2f(1.8) + f(2)]

To evaluate this, we need to calculate the values of f(x) at each point. Let's calculate f(x) = 1/โˆš(1+x^3) for each of the x values:
f(0) = 1/โˆš(1+0^3) = 1
f(0.2) = 1/โˆš(1+0.2^3) = 0.9759
f(0.4) = 1/โˆš(1+0.4^3) = 0.9565
...
f(1.8) = 1/โˆš(1+1.8^3) = 0.7400
f(2) = 1/โˆš(1+2^3) = 0.7093

Now, we can substitute these values into the Trapezoidal Rule formula:
โˆซ[0,2] 1/โˆš(1+x^3) dx โ‰ˆ (0.2/2) [1 + 2(0.9759) + 2(0.9565) + ... + 2(0.7400) + 0.7093]
Simplifying this expression will give us the approximate value of the integral.

(b) Midpoint Rule:
The formula for approximating an integral using the Midpoint Rule is:
โˆซ[a,b] f(x) dx โ‰ˆ ฮ”x [f(x1) + f(x2) + ... + f(xn)]
where x1, x2, ..., xn are the midpoints of the subintervals.

In this case, a = 0, b = 2, ฮ”x = 0.2.
Plugging these values into the formula, we get:
โˆซ[0,2] 1/โˆš(1+x^3) dx โ‰ˆ 0.2 [f(0.1) + f(0.3) + f(0.5) + ... + f(1.9)]
To evaluate this, we need to calculate the values of f(x) at each midpoint x.

(c) Simpson's Rule:
The formula for approximating an integral using Simpson's Rule is:
โˆซ[a,b] f(x) dx โ‰ˆ (ฮ”x/3) [f(a) + 4f(x1) + 2f(x2) + 4f(x3) + 2f(x4) + ... + 2f(x(n-2)) + 4f(x(n-1)) + f(b)]
where x1, x2, ..., x(n-1) are the midpoints of the subintervals.

In this case, a = 0, b = 2, ฮ”x = 0.2.
Plugging these values into the formula, we get:
โˆซ[0,2] 1/โˆš(1+x^3) dx โ‰ˆ (0.2/3) [f(0) + 4f(0.2) + 2f(0.4) + 4f(0.6) + ... + 4f(1.8) + 2f(2)]
To evaluate this, we need to calculate the values of f(x) at each x value.

After evaluating the respective formulas, you will obtain approximations of the given integral using the Trapezoidal Rule, Midpoint Rule, and Simpson's Rule with n = 10.