Select The Correct Answer.What Is The \[$ Y \$\]-intercept Of \[$ F(x) = 3^{x+2} \$\]?A. \[$ (9,0) \$\] B. \[$ (0,9) \$\] C. \[$ (0,-9) \$\] D. \[$ (9,-9) \$\]
The y-intercept of a function is a crucial concept in mathematics, particularly in algebra and calculus. It represents the point at which the graph of a function intersects the y-axis. In other words, it is the value of the function when the input (or x-value) is equal to zero. In this article, we will focus on finding the y-intercept of a given function and provide a step-by-step guide on how to select the correct answer.
What is the y-Intercept?
The y-intercept is a point on the graph of a function where the x-coordinate is zero. It is denoted by the symbol (0, y) or (0, f(0)), where y is the value of the function at x = 0. The y-intercept is an important concept in mathematics, as it provides valuable information about the behavior of a function.
Finding the y-Intercept of a Function
To find the y-intercept of a function, we need to substitute x = 0 into the function and evaluate the resulting expression. This will give us the value of the function at x = 0, which is the y-intercept.
Step-by-Step Guide to Finding the y-Intercept
- Substitute x = 0 into the function: Replace x with 0 in the given function.
- Evaluate the resulting expression: Simplify the expression to find the value of the function at x = 0.
- Identify the y-intercept: The resulting value is the y-intercept of the function.
Example: Finding the y-Intercept of f(x) = 3^(x+2)
Let's apply the step-by-step guide to find the y-intercept of the function f(x) = 3^(x+2).
Step 1: Substitute x = 0 into the function
f(0) = 3^(0+2)
Step 2: Evaluate the resulting expression
f(0) = 3^2
Step 3: Identify the y-intercept
f(0) = 9
Therefore, the y-intercept of the function f(x) = 3^(x+2) is (0, 9).
Selecting the Correct Answer
Based on our calculation, the correct answer is:
- B. (0, 9)
The other options are incorrect because they do not match the y-intercept of the function f(x) = 3^(x+2).
Conclusion
In conclusion, finding the y-intercept of a function is a straightforward process that involves substituting x = 0 into the function and evaluating the resulting expression. By following the step-by-step guide provided in this article, you can easily find the y-intercept of any function. Remember to substitute x = 0 into the function, evaluate the resulting expression, and identify the y-intercept. With practice, you will become proficient in finding the y-intercept of various functions.
Frequently Asked Questions
- What is the y-intercept of a function?
- The y-intercept is a point on the graph of a function where the x-coordinate is zero.
- How do I find the y-intercept of a function?
- Substitute x = 0 into the function and evaluate the resulting expression.
- What is the y-intercept of f(x) = 3^(x+2)?
- The y-intercept of f(x) = 3^(x+2) is (0, 9).
Additional Resources
For more information on finding the y-intercept of a function, you can refer to the following resources:
- Algebra textbooks: Most algebra textbooks cover the concept of y-intercept in detail.
- Online resources: Websites such as Khan Academy, Mathway, and Wolfram Alpha provide interactive lessons and examples on finding the y-intercept of a function.
- Mathematical software: Software such as Mathematica and Maple can be used to visualize and analyze the graph of a function, including finding the y-intercept.
Q&A: Finding the y-Intercept of a Function =============================================
In our previous article, we discussed the concept of y-intercept and provided a step-by-step guide on how to find the y-intercept of a function. In this article, we will address some frequently asked questions related to finding the y-intercept of a function.
Q: What is the y-intercept of a function?
A: The y-intercept of a function is a point on the graph of a function where the x-coordinate is zero. It is denoted by the symbol (0, y) or (0, f(0)), where y is the value of the function at x = 0.
Q: How do I find the y-intercept of a function?
A: To find the y-intercept of a function, you need to substitute x = 0 into the function and evaluate the resulting expression. This will give you the value of the function at x = 0, which is the y-intercept.
Q: What is the y-intercept of f(x) = 3^(x+2)?
A: The y-intercept of f(x) = 3^(x+2) is (0, 9). To find this, we substitute x = 0 into the function and evaluate the resulting expression: f(0) = 3^(0+2) = 3^2 = 9.
Q: Can I use a calculator to find the y-intercept of a function?
A: Yes, you can use a calculator to find the y-intercept of a function. Simply substitute x = 0 into the function and evaluate the resulting expression using the calculator.
Q: What if the function is a polynomial or a rational function?
A: If the function is a polynomial or a rational function, you can use the same method to find the y-intercept. Substitute x = 0 into the function and evaluate the resulting expression.
Q: Can I find the y-intercept of a function using a graphing calculator?
A: Yes, you can use a graphing calculator to find the y-intercept of a function. Graph the function and use the calculator to find the point where the graph intersects the y-axis.
Q: What if the function has a variable in the exponent?
A: If the function has a variable in the exponent, you may need to use logarithmic properties to simplify the expression and find the y-intercept.
Q: Can I find the y-intercept of a function using a computer algebra system (CAS)?
A: Yes, you can use a CAS to find the y-intercept of a function. Enter the function into the CAS and use the software to find the point where the graph intersects the y-axis.
Q: What if I'm having trouble finding the y-intercept of a function?
A: If you're having trouble finding the y-intercept of a function, try the following:
- Check your work to make sure you're substituting x = 0 into the function correctly.
- Simplify the expression to make it easier to evaluate.
- Use a calculator or computer algebra system to check your work.
- Ask a teacher or tutor for help.
Conclusion
Finding the y-intercept of a function is an important concept in mathematics, and it can be used to analyze and understand the behavior of a function. By following the step-by-step guide provided in this article, you can easily find the y-intercept of any function. Remember to substitute x = 0 into the function, evaluate the resulting expression, and identify the y-intercept. With practice, you will become proficient in finding the y-intercept of various functions.
Frequently Asked Questions
- What is the y-intercept of a function?
- The y-intercept is a point on the graph of a function where the x-coordinate is zero.
- How do I find the y-intercept of a function?
- Substitute x = 0 into the function and evaluate the resulting expression.
- What is the y-intercept of f(x) = 3^(x+2)?
- The y-intercept of f(x) = 3^(x+2) is (0, 9).
Additional Resources
For more information on finding the y-intercept of a function, you can refer to the following resources:
- Algebra textbooks: Most algebra textbooks cover the concept of y-intercept in detail.
- Online resources: Websites such as Khan Academy, Mathway, and Wolfram Alpha provide interactive lessons and examples on finding the y-intercept of a function.
- Mathematical software: Software such as Mathematica and Maple can be used to visualize and analyze the graph of a function, including finding the y-intercept.