Consider The Following Function On The Given Domain: A ( X ) = ( X − 4 ) 2 + 4 , X ≥ 4 A(x) = (x-4)^2 + 4, \quad X \geq 4 A ( X ) = ( X − 4 ) 2 + 4 , X ≥ 4 Step 1 Of 2: Find A Formula For The Inverse Of The Function On The Given Domain, If Possible.

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Introduction

In this article, we will explore the concept of finding the inverse of a quadratic function on a given domain. The function we will be working with is A(x)=(x4)2+4A(x) = (x-4)^2 + 4, where x4x \geq 4. We will follow a step-by-step approach to find the inverse of this function, if possible.

Step 1: Understanding the Function

The given function is a quadratic function in the form of f(x)=a(xh)2+kf(x) = a(x-h)^2 + k, where aa, hh, and kk are constants. In this case, a=1a = 1, h=4h = 4, and k=4k = 4. The function is defined for x4x \geq 4, which means that the domain of the function is [4,)[4, \infty).

Step 2: Finding the Inverse

To find the inverse of a function, we need to swap the roles of xx and yy and then solve for yy. Let's start by writing the function as y=(x4)2+4y = (x-4)^2 + 4. To find the inverse, we will swap xx and yy to get x=(y4)2+4x = (y-4)^2 + 4.

Solving for y

Now, we need to solve for yy. We can start by subtracting 44 from both sides of the equation to get x4=(y4)2x - 4 = (y-4)^2. Next, we can take the square root of both sides to get x4=y4\sqrt{x - 4} = y - 4. Finally, we can add 44 to both sides to get y=x4+4y = \sqrt{x - 4} + 4.

Domain of the Inverse

Since the original function is defined for x4x \geq 4, the domain of the inverse function will be [4,)[4, \infty). However, we need to check if the inverse function is defined for this domain.

Checking the Inverse

Let's check if the inverse function is defined for x4x \geq 4. We can plug in a value of xx into the inverse function to see if it is defined. For example, let's plug in x=5x = 5. We get y=54+4=1+4=5y = \sqrt{5 - 4} + 4 = \sqrt{1} + 4 = 5. This shows that the inverse function is defined for x4x \geq 4.

Conclusion

In this article, we found the inverse of the quadratic function A(x)=(x4)2+4A(x) = (x-4)^2 + 4 on the given domain x4x \geq 4. The inverse function is y=x4+4y = \sqrt{x - 4} + 4. We also checked that the inverse function is defined for the domain [4,)[4, \infty).

Example

Let's consider an example to illustrate the concept of finding the inverse of a quadratic function. Suppose we have a function f(x)=x2+2x+1f(x) = x^2 + 2x + 1. We can find the inverse of this function by following the same steps as before.

Step 1: Understanding the Function

The function f(x)=x2+2x+1f(x) = x^2 + 2x + 1 is a quadratic function in the form of f(x)=ax2+bx+cf(x) = ax^2 + bx + c, where a=1a = 1, b=2b = 2, and c=1c = 1. The domain of the function is (,)(-\infty, \infty).

Step 2: Finding the Inverse

To find the inverse of the function, we need to swap the roles of xx and yy and then solve for yy. Let's start by writing the function as y=x2+2x+1y = x^2 + 2x + 1. To find the inverse, we will swap xx and yy to get x=y2+2y+1x = y^2 + 2y + 1.

Solving for y

Now, we need to solve for yy. We can start by subtracting 11 from both sides of the equation to get x1=y2+2yx - 1 = y^2 + 2y. Next, we can rearrange the equation to get y2+2y+(x1)=0y^2 + 2y + (x - 1) = 0. We can then use the quadratic formula to solve for yy.

Quadratic Formula

The quadratic formula is given by y=b±b24ac2ay = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}. In this case, a=1a = 1, b=2b = 2, and c=x1c = x - 1. Plugging these values into the quadratic formula, we get y=2±224(1)(x1)2(1)y = \frac{-2 \pm \sqrt{2^2 - 4(1)(x - 1)}}{2(1)}.

Simplifying the Expression

Simplifying the expression, we get y=2±44x+42=2±4x+82=2±2x+22=1±x+2y = \frac{-2 \pm \sqrt{4 - 4x + 4}}{2} = \frac{-2 \pm \sqrt{-4x + 8}}{2} = \frac{-2 \pm 2\sqrt{-x + 2}}{2} = -1 \pm \sqrt{-x + 2}.

Domain of the Inverse

Since the original function is defined for x(,)x \in (-\infty, \infty), the domain of the inverse function will be (,2)(-\infty, 2).

Checking the Inverse

Let's check if the inverse function is defined for x(,2)x \in (-\infty, 2). We can plug in a value of xx into the inverse function to see if it is defined. For example, let's plug in x=0x = 0. We get y=1±0+2=1±2y = -1 \pm \sqrt{-0 + 2} = -1 \pm \sqrt{2}. This shows that the inverse function is defined for x(,2)x \in (-\infty, 2).

Conclusion

In this article, we found the inverse of the quadratic function f(x)=x2+2x+1f(x) = x^2 + 2x + 1 on the given domain x(,)x \in (-\infty, \infty). The inverse function is y=1±x+2y = -1 \pm \sqrt{-x + 2}. We also checked that the inverse function is defined for the domain (,2)(-\infty, 2).

Conclusion

Frequently Asked Questions

In this article, we will answer some frequently asked questions about finding the inverse of a quadratic function.

Q: What is the inverse of a quadratic function?

A: The inverse of a quadratic function is a function that undoes the action of the original function. In other words, if we have a function f(x)f(x) and its inverse f1(x)f^{-1}(x), then f(f1(x))=xf(f^{-1}(x)) = x and f1(f(x))=xf^{-1}(f(x)) = x.

Q: How do I find the inverse of a quadratic function?

A: To find the inverse of a quadratic function, you need to follow these steps:

  1. Write the function in the form y=ax2+bx+cy = ax^2 + bx + c.
  2. Swap the roles of xx and yy to get x=ay2+by+cx = ay^2 + by + c.
  3. Solve for yy by rearranging the equation.
  4. Check if the inverse function is defined for the given domain.

Q: What is the domain of the inverse of a quadratic function?

A: The domain of the inverse of a quadratic function is the set of all values of xx for which the original function is defined.

Q: Can I find the inverse of a quadratic function with a negative leading coefficient?

A: Yes, you can find the inverse of a quadratic function with a negative leading coefficient. However, the inverse function may not be defined for the entire domain of the original function.

Q: How do I check if the inverse function is defined for the given domain?

A: To check if the inverse function is defined for the given domain, you need to plug in a value of xx into the inverse function and see if it is defined. If the inverse function is defined for the given domain, then it is a valid inverse function.

Q: What is the difference between the inverse of a quadratic function and the reciprocal of a quadratic function?

A: The inverse of a quadratic function is a function that undoes the action of the original function, while the reciprocal of a quadratic function is a function that is the reciprocal of the original function. In other words, the inverse of a quadratic function is a function that "reverses" the original function, while the reciprocal of a quadratic function is a function that "flips" the original function.

Q: Can I find the inverse of a quadratic function with a complex coefficient?

A: Yes, you can find the inverse of a quadratic function with a complex coefficient. However, the inverse function may not be defined for the entire domain of the original function.

Q: How do I find the inverse of a quadratic function with a complex coefficient?

A: To find the inverse of a quadratic function with a complex coefficient, you need to follow the same steps as before. However, you may need to use complex numbers and complex arithmetic to solve for yy.

Q: What is the significance of finding the inverse of a quadratic function?

A: Finding the inverse of a quadratic function is important in many areas of mathematics and science, such as algebra, calculus, and physics. It can help you solve equations, model real-world phenomena, and make predictions about the behavior of systems.

Conclusion

In conclusion, finding the inverse of a quadratic function involves swapping the roles of xx and yy and then solving for yy. You can use the quadratic formula to solve for yy and then check if the inverse function is defined for the given domain. The inverse of a quadratic function is a function that undoes the action of the original function, and it can be used to solve equations, model real-world phenomena, and make predictions about the behavior of systems.