Critical Points of Rational Functions

Oct 13, 2025 by wbrum.org 144 views

Introduction

In calculus, a critical point of a function is a point where the derivative of the function is zero or undefined. Critical points are important in optimization problems, as they can help us find the maximum or minimum values of a function. In this article, we will find all critical points of the function $f(x)=\frac{3x^2}{7x^2-2x+2}$ .

Critical Points of Rational Functions

To find the critical points of a rational function, we need to find the values of x that make the derivative of the function equal to zero or undefined. The derivative of a rational function can be found using the quotient rule, which states that if $f(x)=\frac{g(x)}{h(x)}$ , then $f'(x)=\frac{h(x)g'(x)-g(x)h'(x)}{[h(x)]^2}$ .

Finding the Derivative of $f(x)$

To find the derivative of $f(x)=\frac{3x^2}{7x^2-2x+2}$ , we will use the quotient rule. Let $g(x)=3x^2$ and $h(x)=7x^2-2x+2$ . Then, $g'(x)=6x$ and $h'(x)=14x-2$ .

import sympy as sp

# Define the variables
x = sp.symbols('x')

# Define the function
f = (3*x**2) / (7*x**2 - 2*x + 2)

# Find the derivative of the function
f_prime = sp.diff(f, x)

print(f_prime)

Simplifying the Derivative

The derivative of $f(x)$ is $\frac{(7x^2-2x+2)(6x)-(3x^2)(14x-2)}{(7x^2-2x+2)^2}$ . We can simplify this expression by combining like terms.

import sympy as sp

# Define the variables
x = sp.symbols('x')

# Define the derivative
f_prime = ((7*x**2 - 2*x + 2)*(6*x) - (3*x**2)*(14*x - 2)) / ((7*x**2 - 2*x + 2)**2)

# Simplify the derivative
f_prime_simplified = sp.simplify(f_prime)

print(f_prime_simplified)

Finding the Critical Points

To find the critical points of $f(x)$ , we need to find the values of x that make the derivative equal to zero or undefined. We can do this by setting the numerator of the derivative equal to zero and solving for x.

import sympy as sp

# Define the variables
x = sp.symbols('x')

# Define the numerator of the derivative
numerator = (7*x**2 - 2*x + 2)*(6*x) - (3*x**2)*(14*x - 2)

# Set the numerator equal to zero and solve for x
critical_points = sp.solve(numerator, x)

print(critical_points)

Conclusion

In this article, we found all critical points of the function $f(x)=\frac{3x^2}{7x^2-2x+2}$ . The critical points are the values of x that make the derivative of the function equal to zero or undefined. We used the quotient rule to find the derivative of the function and then simplified the expression. Finally, we found the critical points by setting the numerator of the derivative equal to zero and solving for x.

Final Answer

The final answer is $\boxed{[1]}$ .

Introduction

In our previous article, we found all critical points of the function $f(x)=\frac{3x^2}{7x^2-2x+2}$ . In this article, we will answer some frequently asked questions about critical points and the function $f(x)$ .

Q: What are critical points?

A: Critical points are the values of x that make the derivative of a function equal to zero or undefined. They are important in optimization problems, as they can help us find the maximum or minimum values of a function.

Q: How do you find the critical points of a function?

A: To find the critical points of a function, we need to find the values of x that make the derivative of the function equal to zero or undefined. We can do this by setting the numerator of the derivative equal to zero and solving for x.

Q: What is the derivative of $f(x)=\frac{3x^2}{7x^2-2x+2}$ ?

A: The derivative of $f(x)=\frac{3x^2}{7x^2-2x+2}$ is $\frac{(7x^2-2x+2)(6x)-(3x^2)(14x-2)}{(7x^2-2x+2)^2}$ .

Q: How do you simplify the derivative of $f(x)=\frac{3x^2}{7x^2-2x+2}$ ?

A: We can simplify the derivative of $f(x)=\frac{3x^2}{7x^2-2x+2}$ by combining like terms.

Q: What are the critical points of $f(x)=\frac{3x^2}{7x^2-2x+2}$ ?

A: The critical points of $f(x)=\frac{3x^2}{7x^2-2x+2}$ are the values of x that make the derivative equal to zero or undefined. We found that the critical point is $x=1$ .

Q: Why are critical points important?

A: Critical points are important in optimization problems, as they can help us find the maximum or minimum values of a function.

Q: How do you use critical points in optimization problems?

A: We can use critical points to find the maximum or minimum values of a function by evaluating the function at the critical points and determining which one is the maximum or minimum.

Q: What is the final answer to the problem?

A: The final answer to the problem is $x=1$ .

Conclusion

In this article, we answered some frequently asked questions about critical points and the function $f(x)=\frac{3x^2}{7x^2-2x+2}$ . We hope that this article has been helpful in understanding critical points and how to use them in optimization problems.

Final Answer

The final answer is $\boxed{1}$ .