Rewrite By Removing A Factor Of \[$\tan^2(x)\$\] From The Integrand:$\[ \int (\tan (x))^6 \, Dx = \int \tan^4(x) \tan^2(x) \, Dx \\]Rewrite Using The Pythagorean Identity \[$1 + \tan^2 X = \sec^2

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Introduction

When dealing with trigonometric integrals, it's often necessary to manipulate the integrand to simplify the expression and make it easier to evaluate. One common technique is to remove a factor of tan⁑2(x)\tan^2(x) from the integrand, which can be achieved using the Pythagorean identity. In this article, we'll explore how to rewrite the integral ∫(tan⁑(x))6 dx\int (\tan (x))^6 \, dx by removing a factor of tan⁑2(x)\tan^2(x) from the integrand, and we'll use the Pythagorean identity to simplify the expression.

The Pythagorean Identity

The Pythagorean identity is a fundamental concept in trigonometry that relates the sine, cosine, and tangent functions. It states that:

1+tan⁑2x=sec⁑2x1 + \tan^2 x = \sec^2 x

This identity can be used to rewrite the integrand in terms of sec⁑2x\sec^2 x, which can then be substituted back into the original integral.

Removing a Factor of tan⁑2(x)\tan^2(x) from the Integrand

To remove a factor of tan⁑2(x)\tan^2(x) from the integrand, we can use the Pythagorean identity to rewrite the expression in terms of sec⁑2x\sec^2 x. We'll start by rewriting the integrand as follows:

∫(tan⁑(x))6 dx=∫tan⁑4(x)tan⁑2(x) dx\int (\tan (x))^6 \, dx = \int \tan^4(x) \tan^2(x) \, dx

Now, we can use the Pythagorean identity to rewrite the expression in terms of sec⁑2x\sec^2 x. We'll start by rewriting tan⁑2(x)\tan^2(x) in terms of sec⁑2x\sec^2 x:

tan⁑2(x)=1sec⁑2x\tan^2(x) = \frac{1}{\sec^2 x}

Substituting this expression back into the integrand, we get:

∫tan⁑4(x)tan⁑2(x) dx=∫tan⁑4(x)1sec⁑2x dx\int \tan^4(x) \tan^2(x) \, dx = \int \tan^4(x) \frac{1}{\sec^2 x} \, dx

Simplifying the Integrand

Now that we've rewritten the integrand in terms of sec⁑2x\sec^2 x, we can simplify the expression further. We'll start by rewriting tan⁑4(x)\tan^4(x) in terms of sec⁑2x\sec^2 x:

tan⁑4(x)=(1sec⁑2x)2=1sec⁑4x\tan^4(x) = \left(\frac{1}{\sec^2 x}\right)^2 = \frac{1}{\sec^4 x}

Substituting this expression back into the integrand, we get:

∫tan⁑4(x)1sec⁑2x dx=∫1sec⁑4x1sec⁑2x dx\int \tan^4(x) \frac{1}{\sec^2 x} \, dx = \int \frac{1}{\sec^4 x} \frac{1}{\sec^2 x} \, dx

Evaluating the Integral

Now that we've simplified the integrand, we can evaluate the integral. We'll start by combining the two fractions:

∫1sec⁑4x1sec⁑2x dx=∫1sec⁑6x dx\int \frac{1}{\sec^4 x} \frac{1}{\sec^2 x} \, dx = \int \frac{1}{\sec^6 x} \, dx

To evaluate this integral, we can use the substitution u=sec⁑xu = \sec x. This gives us:

du=sec⁑xtan⁑x dxdu = \sec x \tan x \, dx

Substituting this expression back into the integral, we get:

∫1sec⁑6x dx=∫1u6 du\int \frac{1}{\sec^6 x} \, dx = \int \frac{1}{u^6} \, du

Evaluating the Resulting Integral

Now that we've made the substitution, we can evaluate the resulting integral. We'll start by rewriting the integral in terms of uu:

∫1u6 du=∫uβˆ’6 du\int \frac{1}{u^6} \, du = \int u^{-6} \, du

This is a standard integral that can be evaluated using the power rule:

∫uβˆ’6 du=uβˆ’5βˆ’5+C\int u^{-6} \, du = \frac{u^{-5}}{-5} + C

Substituting back u=sec⁑xu = \sec x, we get:

uβˆ’5βˆ’5+C=(sec⁑x)βˆ’5βˆ’5+C\frac{u^{-5}}{-5} + C = \frac{(\sec x)^{-5}}{-5} + C

Conclusion

In this article, we've shown how to rewrite the integral ∫(tan⁑(x))6 dx\int (\tan (x))^6 \, dx by removing a factor of tan⁑2(x)\tan^2(x) from the integrand. We used the Pythagorean identity to rewrite the expression in terms of sec⁑2x\sec^2 x, and then simplified the integrand further. Finally, we evaluated the resulting integral using the substitution u=sec⁑xu = \sec x. This approach provides a comprehensive and step-by-step solution to the problem, and can be applied to a wide range of trigonometric integrals.

Final Answer

The final answer is βˆ’15sec⁑5x+C\boxed{-\frac{1}{5\sec^5 x} + C}.

Discussion

The Pythagorean identity is a fundamental concept in trigonometry that relates the sine, cosine, and tangent functions. It states that:

1+tan⁑2x=sec⁑2x1 + \tan^2 x = \sec^2 x

This identity can be used to rewrite the integrand in terms of sec⁑2x\sec^2 x, which can then be substituted back into the original integral.

Example

Let's consider an example to illustrate the concept. Suppose we want to evaluate the integral ∫(tan⁑(x))6 dx\int (\tan (x))^6 \, dx. We can use the Pythagorean identity to rewrite the expression in terms of sec⁑2x\sec^2 x:

∫(tan⁑(x))6 dx=∫tan⁑4(x)tan⁑2(x) dx\int (\tan (x))^6 \, dx = \int \tan^4(x) \tan^2(x) \, dx

Now, we can use the Pythagorean identity to rewrite the expression in terms of sec⁑2x\sec^2 x:

tan⁑2(x)=1sec⁑2x\tan^2(x) = \frac{1}{\sec^2 x}

Substituting this expression back into the integrand, we get:

∫tan⁑4(x)tan⁑2(x) dx=∫tan⁑4(x)1sec⁑2x dx\int \tan^4(x) \tan^2(x) \, dx = \int \tan^4(x) \frac{1}{\sec^2 x} \, dx

Step-by-Step Solution

Here's a step-by-step solution to the problem:

  1. Rewrite the integrand in terms of sec⁑2x\sec^2 x using the Pythagorean identity.
  2. Simplify the integrand further by rewriting tan⁑4(x)\tan^4(x) in terms of sec⁑2x\sec^2 x.
  3. Evaluate the resulting integral using the substitution u=sec⁑xu = \sec x.
  4. Substitute back u=sec⁑xu = \sec x to get the final answer.

Key Concepts

  • The Pythagorean identity is a fundamental concept in trigonometry that relates the sine, cosine, and tangent functions.
  • The Pythagorean identity can be used to rewrite the integrand in terms of sec⁑2x\sec^2 x.
  • The substitution u=sec⁑xu = \sec x can be used to evaluate the resulting integral.

Applications

  • The Pythagorean identity can be used to rewrite a wide range of trigonometric integrals.
  • The substitution u=sec⁑xu = \sec x can be used to evaluate a wide range of trigonometric integrals.

Limitations

  • The Pythagorean identity only applies to trigonometric functions.
  • The substitution u=sec⁑xu = \sec x only applies to trigonometric integrals.

Future Work

  • Investigate the use of the Pythagorean identity in other areas of mathematics.
  • Investigate the use of the substitution u=sec⁑xu = \sec x in other areas of mathematics.

Conclusion

In this article, we've shown how to rewrite the integral ∫(tan⁑(x))6 dx\int (\tan (x))^6 \, dx by removing a factor of tan⁑2(x)\tan^2(x) from the integrand. We used the Pythagorean identity to rewrite the expression in terms of sec⁑2x\sec^2 x, and then simplified the integrand further. Finally, we evaluated the resulting integral using the substitution u=sec⁑xu = \sec x. This approach provides a comprehensive and step-by-step solution to the problem, and can be applied to a wide range of trigonometric integrals.

Introduction

In our previous article, we showed how to rewrite the integral ∫(tan⁑(x))6 dx\int (\tan (x))^6 \, dx by removing a factor of tan⁑2(x)\tan^2(x) from the integrand. We used the Pythagorean identity to rewrite the expression in terms of sec⁑2x\sec^2 x, and then simplified the integrand further. Finally, we evaluated the resulting integral using the substitution u=sec⁑xu = \sec x. In this article, we'll answer some common questions related to this topic.

Q: What is the Pythagorean identity?

A: The Pythagorean identity is a fundamental concept in trigonometry that relates the sine, cosine, and tangent functions. It states that:

1+tan⁑2x=sec⁑2x1 + \tan^2 x = \sec^2 x

Q: How can I use the Pythagorean identity to rewrite the integrand?

A: To use the Pythagorean identity to rewrite the integrand, you can start by rewriting tan⁑2(x)\tan^2(x) in terms of sec⁑2x\sec^2 x:

tan⁑2(x)=1sec⁑2x\tan^2(x) = \frac{1}{\sec^2 x}

Then, you can substitute this expression back into the integrand to get:

∫tan⁑4(x)tan⁑2(x) dx=∫tan⁑4(x)1sec⁑2x dx\int \tan^4(x) \tan^2(x) \, dx = \int \tan^4(x) \frac{1}{\sec^2 x} \, dx

Q: How can I simplify the integrand further?

A: To simplify the integrand further, you can rewrite tan⁑4(x)\tan^4(x) in terms of sec⁑2x\sec^2 x:

tan⁑4(x)=(1sec⁑2x)2=1sec⁑4x\tan^4(x) = \left(\frac{1}{\sec^2 x}\right)^2 = \frac{1}{\sec^4 x}

Then, you can substitute this expression back into the integrand to get:

∫tan⁑4(x)1sec⁑2x dx=∫1sec⁑4x1sec⁑2x dx\int \tan^4(x) \frac{1}{\sec^2 x} \, dx = \int \frac{1}{\sec^4 x} \frac{1}{\sec^2 x} \, dx

Q: How can I evaluate the resulting integral?

A: To evaluate the resulting integral, you can use the substitution u=sec⁑xu = \sec x. This gives you:

du=sec⁑xtan⁑x dxdu = \sec x \tan x \, dx

Then, you can substitute this expression back into the integral to get:

∫1sec⁑4x1sec⁑2x dx=∫1u6 du\int \frac{1}{\sec^4 x} \frac{1}{\sec^2 x} \, dx = \int \frac{1}{u^6} \, du

Q: What is the final answer?

A: The final answer is βˆ’15sec⁑5x+C\boxed{-\frac{1}{5\sec^5 x} + C}.

Q: What are some common applications of the Pythagorean identity?

A: The Pythagorean identity has many common applications in trigonometry, including:

  • Rewriting the integrand in terms of sec⁑2x\sec^2 x
  • Simplifying the integrand further
  • Evaluating the resulting integral using the substitution u=sec⁑xu = \sec x

Q: What are some common limitations of the Pythagorean identity?

A: The Pythagorean identity has some common limitations, including:

  • Only applying to trigonometric functions
  • Only applying to trigonometric integrals

Q: What are some common future directions for research in this area?

A: Some common future directions for research in this area include:

  • Investigating the use of the Pythagorean identity in other areas of mathematics
  • Investigating the use of the substitution u=sec⁑xu = \sec x in other areas of mathematics

Conclusion

In this article, we've answered some common questions related to removing a factor of tan⁑2(x)\tan^2(x) from the integrand. We've shown how to use the Pythagorean identity to rewrite the integrand, simplify the integrand further, and evaluate the resulting integral using the substitution u=sec⁑xu = \sec x. This approach provides a comprehensive and step-by-step solution to the problem, and can be applied to a wide range of trigonometric integrals.

Final Answer

The final answer is βˆ’15sec⁑5x+C\boxed{-\frac{1}{5\sec^5 x} + C}.

Discussion

The Pythagorean identity is a fundamental concept in trigonometry that relates the sine, cosine, and tangent functions. It states that:

1+tan⁑2x=sec⁑2x1 + \tan^2 x = \sec^2 x

This identity can be used to rewrite the integrand in terms of sec⁑2x\sec^2 x, which can then be substituted back into the original integral.

Example

Let's consider an example to illustrate the concept. Suppose we want to evaluate the integral ∫(tan⁑(x))6 dx\int (\tan (x))^6 \, dx. We can use the Pythagorean identity to rewrite the expression in terms of sec⁑2x\sec^2 x:

∫(tan⁑(x))6 dx=∫tan⁑4(x)tan⁑2(x) dx\int (\tan (x))^6 \, dx = \int \tan^4(x) \tan^2(x) \, dx

Now, we can use the Pythagorean identity to rewrite the expression in terms of sec⁑2x\sec^2 x:

tan⁑2(x)=1sec⁑2x\tan^2(x) = \frac{1}{\sec^2 x}

Substituting this expression back into the integrand, we get:

∫tan⁑4(x)tan⁑2(x) dx=∫tan⁑4(x)1sec⁑2x dx\int \tan^4(x) \tan^2(x) \, dx = \int \tan^4(x) \frac{1}{\sec^2 x} \, dx

Step-by-Step Solution

Here's a step-by-step solution to the problem:

  1. Rewrite the integrand in terms of sec⁑2x\sec^2 x using the Pythagorean identity.
  2. Simplify the integrand further by rewriting tan⁑4(x)\tan^4(x) in terms of sec⁑2x\sec^2 x.
  3. Evaluate the resulting integral using the substitution u=sec⁑xu = \sec x.
  4. Substitute back u=sec⁑xu = \sec x to get the final answer.

Key Concepts

  • The Pythagorean identity is a fundamental concept in trigonometry that relates the sine, cosine, and tangent functions.
  • The Pythagorean identity can be used to rewrite the integrand in terms of sec⁑2x\sec^2 x.
  • The substitution u=sec⁑xu = \sec x can be used to evaluate the resulting integral.

Applications

  • The Pythagorean identity can be used to rewrite a wide range of trigonometric integrals.
  • The substitution u=sec⁑xu = \sec x can be used to evaluate a wide range of trigonometric integrals.

Limitations

  • The Pythagorean identity only applies to trigonometric functions.
  • The substitution u=sec⁑xu = \sec x only applies to trigonometric integrals.

Future Work

  • Investigate the use of the Pythagorean identity in other areas of mathematics.
  • Investigate the use of the substitution u=sec⁑xu = \sec x in other areas of mathematics.