Solve For \[$ X \$\].$\[ \sqrt[3]{x-8} = -3 \\]

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Introduction

Cubic equations are a fundamental concept in mathematics, and solving them can be a challenging task. In this article, we will focus on solving cubic equations that involve cube roots. We will use the given equation x−83=−3\sqrt[3]{x-8} = -3 as an example and walk you through the step-by-step process of finding the value of x.

Understanding the Equation

The given equation is x−83=−3\sqrt[3]{x-8} = -3. This equation involves a cube root, which means that the value inside the cube root must be equal to the cube of the value on the other side of the equation. In this case, the cube of -3 is -27.

Step 1: Cube Both Sides of the Equation

To get rid of the cube root, we need to cube both sides of the equation. This will give us:

(x−83)3=(−3)3\left(\sqrt[3]{x-8}\right)^3 = (-3)^3

Using the property of exponents, we can simplify the left-hand side of the equation:

x−8=−27x-8 = -27

Step 2: Add 8 to Both Sides of the Equation

Now that we have the equation x−8=−27x-8 = -27, we can add 8 to both sides to isolate the variable x:

x−8+8=−27+8x-8+8 = -27+8

This simplifies to:

x=−19x = -19

Conclusion

In this article, we have solved the cubic equation x−83=−3\sqrt[3]{x-8} = -3 using the step-by-step process of cubing both sides of the equation and adding 8 to both sides. We have found that the value of x is -19.

Tips and Tricks

  • When solving cubic equations, it's essential to remember that the cube root of a number is the number that, when cubed, gives the original number.
  • To get rid of the cube root, you can cube both sides of the equation.
  • When adding or subtracting numbers, make sure to add or subtract the same value from both sides of the equation.

Real-World Applications

Cubic equations have numerous real-world applications, including:

  • Physics: Cubic equations are used to describe the motion of objects under the influence of gravity.
  • Engineering: Cubic equations are used to design and optimize systems, such as bridges and buildings.
  • Computer Science: Cubic equations are used in algorithms and data structures to solve complex problems.

Common Mistakes to Avoid

  • Not cubing both sides of the equation: Failing to cube both sides of the equation can lead to incorrect solutions.
  • Not adding or subtracting the same value from both sides: Failing to add or subtract the same value from both sides of the equation can lead to incorrect solutions.

Conclusion

Introduction

In our previous article, we discussed the step-by-step process of solving cubic equations. However, we understand that sometimes, it's easier to learn through questions and answers. In this article, we will provide a Q&A guide to help you better understand how to solve cubic equations.

Q: What is a cubic equation?

A: A cubic equation is a polynomial equation of degree three, which means that the highest power of the variable (usually x) is three. Cubic equations can be written in the form ax^3 + bx^2 + cx + d = 0, where a, b, c, and d are constants.

Q: How do I know if an equation is a cubic equation?

A: To determine if an equation is a cubic equation, look for the highest power of the variable. If the highest power is three, then the equation is a cubic equation.

Q: What is the cube root of a number?

A: The cube root of a number is the number that, when cubed, gives the original number. For example, the cube root of 27 is 3, because 3^3 = 27.

Q: How do I cube both sides of an equation?

A: To cube both sides of an equation, you need to multiply both sides by themselves three times. For example, if you have the equation x = 2, then cubing both sides would give you x^3 = 2^3.

Q: What is the difference between cubing and squaring?

A: Cubing a number means multiplying it by itself three times, while squaring a number means multiplying it by itself two times.

Q: Can I use the same techniques to solve quadratic equations?

A: No, the techniques used to solve cubic equations are different from those used to solve quadratic equations. Quadratic equations can be solved using the quadratic formula, while cubic equations require the use of cube roots and other techniques.

Q: What are some common mistakes to avoid when solving cubic equations?

A: Some common mistakes to avoid when solving cubic equations include:

  • Not cubing both sides of the equation
  • Not adding or subtracting the same value from both sides of the equation
  • Not checking for extraneous solutions

Q: How do I check for extraneous solutions?

A: To check for extraneous solutions, plug the solution back into the original equation and see if it's true. If it's not true, then the solution is extraneous.

Q: Can I use a calculator to solve cubic equations?

A: Yes, you can use a calculator to solve cubic equations. However, it's always a good idea to check your work by hand to make sure the solution is correct.

Conclusion

Solving cubic equations can be a challenging task, but with the right techniques and a little practice, you can become proficient in solving them. In this Q&A guide, we have provided answers to some common questions about solving cubic equations. Remember to cube both sides of the equation, add or subtract the same value from both sides, and check for extraneous solutions to avoid common mistakes.

Additional Resources

  • Online tutorials: There are many online tutorials and videos that can help you learn how to solve cubic equations.
  • Practice problems: Practice solving cubic equations with different types of problems to help you become more confident in your abilities.
  • Math textbooks: Math textbooks can provide a comprehensive overview of solving cubic equations and other mathematical concepts.

Final Tips

  • Practice regularly: The more you practice solving cubic equations, the more confident you will become in your abilities.
  • Use online resources: There are many online resources available to help you learn how to solve cubic equations.
  • Check your work: Always check your work by hand to make sure the solution is correct.