Integrating ∫cos(x)^2*tan(x)^3dx using u-substitution and integration by parts

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Now, use u-substitution with u = cos(x), du = -sin(x)dxThe integral becomes:\displaystyle \int\frac{1}{u}\,du-\int u\,duSimplifying and integrating, we get:\displaystyle \ln|\cos(x)|-\frac{1}{2}\cos^2(x)+CIn summary, the integral of cos(x)^2*tan(x)^3dx can be solved using integration by parts and u-substitution, resulting in the simplified expression of ln|cos(x)|-0.5cos^2(x)+C.
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Homework Statement


∫cos(x)^2*tan(x)^3dx

Homework Equations


The Attempt at a Solution



Were learning Integration by parts and u substitution but this one I can't figure out. I tried making it ∫cos(x)*(sin(x)^3)/(cos(x)^3)dx and then ∫tan(x)*sin(x)^2 but I don't know if I'm going in the right direction because I don't know how to solve from here.
 
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NWeid1 said:

Homework Statement


∫cos(x)^2*tan(x)^3dx

Homework Equations



The Attempt at a Solution



Were learning Integration by parts and u substitution but this one I can't figure out. I tried making it ∫(cos(x))^2*(sin(x)^3)/(cos(x)^3)dx and then ∫tan(x)*sin(x)^2 but I don't know if I'm going in the right direction because I don't know how to solve from here.
That should be [itex]\displaystyle \int\frac{\cos^2(x)\sin^3(x)}{\cos^3(x)}\,dx[/itex]

The integrand can be simplified to:
[itex]\displaystyle \frac{\sin^3(x)}{\cos(x)}[/itex]​
Then change sin3(x) to (sin(x))(1-cos2(x))

The integrand becomes:
[itex]\displaystyle \frac{\sin(x)}{\cos(x)}-\sin(x)\cos(x)[/itex]​
 

FAQ: Integrating ∫cos(x)^2*tan(x)^3dx using u-substitution and integration by parts

What is the integral of cos(x)^2 * tan(x)^3dx?

The integral of cos(x)^2 * tan(x)^3dx is equal to (cos(x)^2 * tan(x)^2)/2 + ln|cos(x)| + C.

What is the purpose of using integration to solve this equation?

The purpose of using integration is to find the area under the curve represented by the function cos(x)^2 * tan(x)^3dx. This can be useful in solving real-world problems in fields such as physics and engineering.

What are the steps to solving this integral?

The steps to solving this integral involve using integration techniques such as substitution and integration by parts. First, substitute u = cos(x) and du = -sin(x)dx. Then, use integration by parts with u = tan(x)^3 and dv = cos(x)dx. Finally, use the trigonometric identity tan(x)^2 = sec(x)^2 - 1 to simplify the integral.

Can this integral be solved using any other methods besides integration?

Yes, this integral can also be solved using techniques such as trigonometric identities and partial fractions. However, integration is the most efficient and commonly used method for solving this type of integral.

What are some applications of integrals in real-world scenarios?

Integrals have many applications in fields such as physics, engineering, and economics. They can be used to calculate distances, volumes, and areas, as well as solve problems involving rates of change and optimization.

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