Given $f(x) = -x^2 - 14$, Find $f(6)$.

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Introduction


In mathematics, quadratic functions are a fundamental concept in algebra and calculus. They are used to model various real-world phenomena, such as the trajectory of a projectile, the growth of a population, and the motion of an object under the influence of a force. In this article, we will focus on finding the value of a quadratic function at a specific point, using the given function $f(x) = -x^2 - 14$ as an example.

Understanding Quadratic Functions


A quadratic function is a polynomial function of degree two, which means the highest power of the variable (in this case, x) is two. The general form of a quadratic function is $f(x) = ax^2 + bx + c$, where a, b, and c are constants. In our example, the function is $f(x) = -x^2 - 14$, where a = -1, b = 0, and c = -14.

Finding the Value of a Quadratic Function


To find the value of a quadratic function at a specific point, we need to substitute the value of x into the function and simplify the expression. In this case, we want to find $f(6)$, which means we need to substitute x = 6 into the function.

Step 1: Substitute x = 6 into the Function


f(6)=−(6)2−14f(6) = -(6)^2 - 14

Step 2: Simplify the Expression


To simplify the expression, we need to evaluate the exponent and then multiply the result by the coefficient.

f(6)=−36−14f(6) = -36 - 14

Step 3: Combine Like Terms


Now, we need to combine the two terms to get the final result.

f(6)=−50f(6) = -50

Conclusion


In this article, we have shown how to find the value of a quadratic function at a specific point using the given function $f(x) = -x^2 - 14$ as an example. We have followed a step-by-step approach to substitute x = 6 into the function, simplify the expression, and combine like terms to get the final result. This process can be applied to any quadratic function to find its value at a specific point.

Example Use Cases


Quadratic functions have many real-world applications, including:

  • Projectile Motion: The trajectory of a projectile under the influence of gravity can be modeled using a quadratic function.
  • Population Growth: The growth of a population over time can be modeled using a quadratic function.
  • Motion Under a Force: The motion of an object under the influence of a force can be modeled using a quadratic function.

Tips and Tricks


When working with quadratic functions, it's essential to remember the following tips and tricks:

  • Use the correct order of operations: When simplifying expressions, make sure to follow the correct order of operations (PEMDAS: Parentheses, Exponents, Multiplication and Division, and Addition and Subtraction).
  • Combine like terms: When combining like terms, make sure to combine the coefficients and the variables separately.
  • Check your work: Always check your work to ensure that the final result is correct.

Conclusion


In conclusion, finding the value of a quadratic function at a specific point is a straightforward process that involves substituting the value of x into the function, simplifying the expression, and combining like terms. By following these steps and using the correct order of operations, you can find the value of any quadratic function at a specific point.

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Introduction


In our previous article, we discussed how to find the value of a quadratic function at a specific point using the given function $f(x) = -x^2 - 14$ as an example. In this article, we will answer some frequently asked questions about quadratic functions to help you better understand this important concept in mathematics.

Q&A


Q: What is a quadratic function?

A: A quadratic function is a polynomial function of degree two, which means the highest power of the variable (in this case, x) is two. The general form of a quadratic function is $f(x) = ax^2 + bx + c$, where a, b, and c are constants.

Q: How do I find the value of a quadratic function at a specific point?

A: To find the value of a quadratic function at a specific point, you need to substitute the value of x into the function and simplify the expression. For example, to find $f(6)$, you would substitute x = 6 into the function $f(x) = -x^2 - 14$ and simplify the expression.

Q: What is the difference between a quadratic function and a linear function?

A: A linear function is a polynomial function of degree one, which means the highest power of the variable (in this case, x) is one. The general form of a linear function is $f(x) = ax + b$, where a and b are constants. Quadratic functions, on the other hand, have a degree of two, which means the highest power of the variable is two.

Q: Can quadratic functions be used to model real-world phenomena?

A: Yes, quadratic functions can be used to model various real-world phenomena, such as the trajectory of a projectile, the growth of a population, and the motion of an object under the influence of a force.

Q: How do I determine the vertex of a quadratic function?

A: The vertex of a quadratic function is the point at which the function reaches its maximum or minimum value. To determine the vertex, you can use the formula $x = -\frac{b}{2a}$, where a and b are the coefficients of the quadratic function.

Q: Can quadratic functions be used to solve problems in physics and engineering?

A: Yes, quadratic functions are widely used in physics and engineering to solve problems involving motion, energy, and other physical quantities.

Q: How do I graph a quadratic function?

A: To graph a quadratic function, you can use a graphing calculator or a computer program to plot the function. You can also use a table of values to create a graph by hand.

Example Problems


Here are some example problems to help you practice finding the value of a quadratic function at a specific point:

  • Find $f(3)$ for the function $f(x) = 2x^2 - 5x + 1$.
  • Find $f(-2)$ for the function $f(x) = -x^2 + 4x - 3$.
  • Find $f(0)$ for the function $f(x) = x^2 + 2x - 1$.

Tips and Tricks


Here are some tips and tricks to help you work with quadratic functions:

  • Use the correct order of operations: When simplifying expressions, make sure to follow the correct order of operations (PEMDAS: Parentheses, Exponents, Multiplication and Division, and Addition and Subtraction).
  • Combine like terms: When combining like terms, make sure to combine the coefficients and the variables separately.
  • Check your work: Always check your work to ensure that the final result is correct.

Conclusion


In conclusion, quadratic functions are an important concept in mathematics that can be used to model various real-world phenomena. By understanding how to find the value of a quadratic function at a specific point, you can solve problems in physics, engineering, and other fields. We hope this Q&A article has helped you better understand quadratic functions and how to work with them.