Which Statement Best Describes How To Determine Whether F ( X ) = X 4 − X 3 F(x)=x^4-x^3 F ( X ) = X 4 − X 3 Is An Even Function?A. Determine Whether ( − X ) 4 − ( − X ) 3 (-x)^4-(-x)^3 ( − X ) 4 − ( − X ) 3 Is Equivalent To X 4 − X 3 X^4-x^3 X 4 − X 3 .B. Determine Whether ( − X ) 4 − ( − X ) 3 (-x)^4-(-x)^3 ( − X ) 4 − ( − X ) 3 Is Equivalent To

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Understanding Even Functions


In mathematics, an even function is a function where f(x)=f(x)f(-x) = f(x) for all x in the domain of the function. This means that if we replace x with -x in the function, the output remains the same. Even functions have symmetry about the y-axis, and they are often represented by functions with only even powers of x.

The Given Function


The given function is f(x)=x4x3f(x) = x^4 - x^3. To determine whether this function is even, we need to check if f(x)=f(x)f(-x) = f(x).

Option A: Determining Equivalence


Option A suggests that we determine whether (x)4(x)3(-x)^4 - (-x)^3 is equivalent to x4x3x^4 - x^3. Let's evaluate this option.

Expanding (x)4(-x)^4 and (x)3(-x)^3


When we expand (x)4(-x)^4, we get (x)4=x4(-x)^4 = x^4 because the power of 4 is even, and the negative sign is eliminated. Similarly, when we expand (x)3(-x)^3, we get (x)3=x3(-x)^3 = -x^3 because the power of 3 is odd, and the negative sign is preserved.

Substituting the Expanded Terms


Now, let's substitute the expanded terms into the expression (x)4(x)3(-x)^4 - (-x)^3. We get:

(x)4(x)3=x4(x3)(-x)^4 - (-x)^3 = x^4 - (-x^3)

Simplifying the Expression


When we simplify the expression, we get:

x4(x3)=x4+x3x^4 - (-x^3) = x^4 + x^3

Comparing the Results


Now, let's compare the result we obtained in Option A with the original function f(x)=x4x3f(x) = x^4 - x^3. We can see that the two expressions are not equivalent.

Conclusion


Based on the analysis, we can conclude that Option A is not the correct approach to determine whether the given function is even.

Option B: Determining Equivalence


Option B suggests that we determine whether (x)4(x)3(-x)^4 - (-x)^3 is equivalent to f(x)=x4x3f(x) = x^4 - x^3. Let's evaluate this option.

Expanding (x)4(-x)^4 and (x)3(-x)^3


As we did in Option A, we can expand (x)4(-x)^4 and (x)3(-x)^3 as follows:

(x)4=x4(-x)^4 = x^4

(x)3=x3(-x)^3 = -x^3

Substituting the Expanded Terms


Now, let's substitute the expanded terms into the expression (x)4(x)3(-x)^4 - (-x)^3. We get:

(x)4(x)3=x4(x3)(-x)^4 - (-x)^3 = x^4 - (-x^3)

Simplifying the Expression


When we simplify the expression, we get:

x4(x3)=x4+x3x^4 - (-x^3) = x^4 + x^3

Comparing the Results


Now, let's compare the result we obtained in Option B with the original function f(x)=x4x3f(x) = x^4 - x^3. We can see that the two expressions are not equivalent.

Conclusion


Based on the analysis, we can conclude that Option B is not the correct approach to determine whether the given function is even.

The Correct Approach


To determine whether the given function is even, we need to check if f(x)=f(x)f(-x) = f(x). Let's evaluate this condition.

Evaluating f(x)f(-x)


When we substitute x-x into the function f(x)=x4x3f(x) = x^4 - x^3, we get:

f(x)=(x)4(x)3f(-x) = (-x)^4 - (-x)^3

Expanding (x)4(-x)^4 and (x)3(-x)^3


As we did earlier, we can expand (x)4(-x)^4 and (x)3(-x)^3 as follows:

(x)4=x4(-x)^4 = x^4

(x)3=x3(-x)^3 = -x^3

Substituting the Expanded Terms


Now, let's substitute the expanded terms into the expression f(x)f(-x). We get:

f(x)=x4(x3)f(-x) = x^4 - (-x^3)

Simplifying the Expression


When we simplify the expression, we get:

f(x)=x4+x3f(-x) = x^4 + x^3

Comparing the Results


Now, let's compare the result we obtained in the correct approach with the original function f(x)=x4x3f(x) = x^4 - x^3. We can see that the two expressions are not equivalent.

Conclusion


Based on the analysis, we can conclude that the given function f(x)=x4x3f(x) = x^4 - x^3 is not an even function.

Final Answer


The final answer is: A

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Understanding Even Functions


In mathematics, an even function is a function where f(x)=f(x)f(-x) = f(x) for all x in the domain of the function. This means that if we replace x with -x in the function, the output remains the same. Even functions have symmetry about the y-axis, and they are often represented by functions with only even powers of x.

Q&A: Even Functions


Q: What is an even function?


A: An even function is a function where f(x)=f(x)f(-x) = f(x) for all x in the domain of the function.

Q: How do I determine if a function is even?


A: To determine if a function is even, you need to check if f(x)=f(x)f(-x) = f(x). If the function satisfies this condition, then it is an even function.

Q: What are some examples of even functions?


A: Some examples of even functions include:

  • f(x)=x2f(x) = x^2
  • f(x)=x4f(x) = x^4
  • f(x)=sin2(x)f(x) = \sin^2(x)

Q: What are some examples of functions that are not even?


A: Some examples of functions that are not even include:

  • f(x)=x3f(x) = x^3
  • f(x)=x2+xf(x) = x^2 + x
  • f(x)=sin(x)f(x) = \sin(x)

Q: Can a function be both even and odd?


A: No, a function cannot be both even and odd. If a function is even, then it satisfies the condition f(x)=f(x)f(-x) = f(x), and if it is odd, then it satisfies the condition f(x)=f(x)f(-x) = -f(x).

Q: How do I graph an even function?


A: To graph an even function, you can use the following steps:

  1. Find the x-intercepts of the function.
  2. Find the y-intercept of the function.
  3. Plot the x-intercepts and the y-intercept on a coordinate plane.
  4. Draw a smooth curve through the points, making sure that the curve is symmetric about the y-axis.

Q: What are some real-world applications of even functions?


A: Even functions have many real-world applications, including:

  • Physics: Even functions are used to describe the motion of objects in physics, such as the motion of a pendulum.
  • Engineering: Even functions are used to design and analyze systems, such as electrical circuits and mechanical systems.
  • Computer Science: Even functions are used in algorithms and data structures, such as sorting and searching.

Conclusion


In conclusion, even functions are an important concept in mathematics, and they have many real-world applications. By understanding even functions, you can better analyze and solve problems in physics, engineering, and computer science.

Final Answer


The final answer is: A