Identify Integral: Identify the integral to be solved.We are given the integral I=∫(1−2r4−2r+1)dr. Our goal is to find the antiderivative of this function.
Simplify Integral: Simplify the integral by breaking it into two separate integrals.I=∫1−2r4dr−∫1−2r2r+1dr
Solve First Integral: Solve the first integral ∫(1−2r4)dr. Let u=1−2r, then du=−2dr, or dr=−2du. Substitute into the integral: ∫(u4)(−21)du=−2∫(u1)du=−2ln∣u∣+C1 Replace u with 1−2r: −2ln∣1−2r∣+C1
Solve Second Integral: Solve the second integral ∫(2r+1/(1−2r))dr. This integral is more complex and may require a substitution or partial fractions. However, we notice that the derivative of 2r+1 is 2, which is related to the denominator 1−2r. This suggests a substitution might work. Let u=2r+1, then du=2dr, or dr=du/2. Substitute into the integral: ∫(u/(1−u/2))⋅(1/2)du
Simplify Integral: Simplify the integral ∫(u/(1−u/2))⋅(1/2)du. We can rewrite the integral as (1/2)∫(u/(1−u/2))du. Now, we need to simplify the denominator: 1−u/2=(2−u)/2. The integral becomes (1/2)∫(u⋅2/(2−u))du=∫(u/(2−u))du.
Solve Integral: Solve the integral ∫(u/(2−u))du. This integral can be solved by a simple substitution or by recognizing it as a standard integral form. However, upon reviewing the previous steps, we realize that there has been a mistake in the substitution process. The denominator should have been (2/u−1) instead of (1−u/2) after the substitution. This is a critical error that affects the solution.
More problems from Find indefinite integrals using the substitution and by parts