Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

int((4-sqrt(2r+1)))/(1-2r)dr

(42r+1)12rdr \int \frac{(4-\sqrt{2 r+1})}{1-2 r} d r

Full solution

Q. (42r+1)12rdr \int \frac{(4-\sqrt{2 r+1})}{1-2 r} d r
  1. Identify Integral: Identify the integral to be solved.\newlineWe are given the integral I=(42r+112r)drI = \int\left(\frac{4 - \sqrt{2r + 1}}{1 - 2r}\right) dr. Our goal is to find the antiderivative of this function.
  2. Simplify Integral: Simplify the integral by breaking it into two separate integrals.\newlineI=412rdr2r+112rdrI = \int\frac{4}{1 - 2r} \, dr - \int\frac{\sqrt{2r + 1}}{1 - 2r} \, dr
  3. Solve First Integral: Solve the first integral (412r)dr\int\left(\frac{4}{1 - 2r}\right) dr. Let u=12ru = 1 - 2r, then du=2drdu = -2 dr, or dr=du2dr = -\frac{du}{2}. Substitute into the integral: (4u)(12)du=2(1u)du=2lnu+C1\int\left(\frac{4}{u}\right) \left(-\frac{1}{2}\right) du = -2 \int\left(\frac{1}{u}\right) du = -2 \ln|u| + C_1 Replace uu with 12r1 - 2r: 2ln12r+C1-2 \ln|1 - 2r| + C_1
  4. Solve Second Integral: Solve the second integral (2r+1/(12r))dr\int(\sqrt{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+12r + 1 is 22, which is related to the denominator 12r1 - 2r. This suggests a substitution might work. Let u=2r+1u = 2r + 1, then du=2drdu = 2 \, dr, or dr=du/2dr = du/2. Substitute into the integral: (u/(1u/2))(1/2)du\int(\sqrt{u} / (1 - u/2)) \cdot (1/2) \, du
  5. Simplify Integral: Simplify the integral (u/(1u/2))(1/2)du\int(\sqrt{u} / (1 - u/2)) \cdot (1/2) \, du. We can rewrite the integral as (1/2)(u/(1u/2))du(1/2) \int(\sqrt{u} / (1 - u/2)) \, du. Now, we need to simplify the denominator: 1u/2=(2u)/21 - u/2 = (2 - u)/2. The integral becomes (1/2)(u2/(2u))du=(u/(2u))du(1/2) \int(\sqrt{u} \cdot 2 / (2 - u)) \, du = \int(\sqrt{u} / (2 - u)) \, du.
  6. Solve Integral: Solve the integral (u/(2u))du\int(\sqrt{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/u1)(2/u - 1) instead of (1u/2)(1 - u/2) after the substitution. This is a critical error that affects the solution.