Shaikh Is Converting A Quadratic Function From Standard Form To Vertex Form. She Is Making A Small, Common Mistake That Is Keeping The Two Functions From Being Equivalent. What Mistake Is Shaikh Making?Given: $\[ Y = X^2 - 8x + 11

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Understanding the Standard and Vertex Forms of Quadratic Functions

Quadratic functions are a fundamental concept in mathematics, and they can be expressed in two main forms: the standard form and the vertex form. The standard form of a quadratic function is given by the equation y=ax2+bx+cy = ax^2 + bx + c, where aa, bb, and cc are constants. On the other hand, the vertex form of a quadratic function is given by the equation y=a(xβˆ’h)2+ky = a(x - h)^2 + k, where (h,k)(h, k) is the vertex of the parabola.

The Importance of Converting Quadratic Functions

Converting a quadratic function from the standard form to the vertex form is an essential skill in mathematics, particularly in algebra and calculus. This conversion is necessary to analyze the properties of the quadratic function, such as its vertex, axis of symmetry, and direction of opening. Moreover, converting a quadratic function from the standard form to the vertex form can help in solving problems related to optimization, physics, and engineering.

Shaikh's Mistake: A Common Pitfall to Avoid

Shaikh is converting a quadratic function from the standard form to the vertex form, but she is making a small, common mistake that is keeping the two functions from being equivalent. The mistake Shaikh is making is related to the process of completing the square, which is a crucial step in converting a quadratic function from the standard form to the vertex form.

Completing the Square: A Step-by-Step Guide

Completing the square is a technique used to convert a quadratic function from the standard form to the vertex form. The process involves rewriting the quadratic function in a way that allows us to easily identify the vertex of the parabola. Here's a step-by-step guide on how to complete the square:

  1. Start with the standard form of the quadratic function: Begin with the standard form of the quadratic function, which is given by the equation y=ax2+bx+cy = ax^2 + bx + c.
  2. Move the constant term to the right-hand side: Move the constant term cc to the right-hand side of the equation by subtracting it from both sides. This gives us the equation yβˆ’c=ax2+bxy - c = ax^2 + bx.
  3. Take half of the coefficient of the linear term: Take half of the coefficient of the linear term bb and square it. This gives us the value (b2)2\left(\frac{b}{2}\right)^2.
  4. Add and subtract the squared value: Add and subtract the squared value (b2)2\left(\frac{b}{2}\right)^2 to the right-hand side of the equation. This gives us the equation yβˆ’c=a(x2+bax)+(b2)2βˆ’(b2)2y - c = a\left(x^2 + \frac{b}{a}x\right) + \left(\frac{b}{2}\right)^2 - \left(\frac{b}{2}\right)^2.
  5. Factor the perfect square trinomial: Factor the perfect square trinomial on the right-hand side of the equation. This gives us the equation yβˆ’c=a(x+b2a)2βˆ’(b2)2+cy - c = a\left(x + \frac{b}{2a}\right)^2 - \left(\frac{b}{2}\right)^2 + c.
  6. Simplify the equation: Simplify the equation by combining like terms. This gives us the equation y=a(x+b2a)2βˆ’(b2)2+cy = a\left(x + \frac{b}{2a}\right)^2 - \left(\frac{b}{2}\right)^2 + c.

Shaikh's Mistake: A Closer Look

Shaikh is making a mistake in the process of completing the square. Specifically, she is not correctly identifying the value of hh, which is the x-coordinate of the vertex of the parabola. Shaikh is incorrectly calculating the value of hh as βˆ’b2a\frac{-b}{2a}, instead of βˆ’b2a\frac{-b}{2a}.

The Correct Value of hh

The correct value of hh is βˆ’b2a\frac{-b}{2a}. This value represents the x-coordinate of the vertex of the parabola. To see why this is the case, let's consider the equation y=a(xβˆ’h)2+ky = a(x - h)^2 + k. Expanding the squared term, we get y=a(x2βˆ’2hx+h2)+ky = a(x^2 - 2hx + h^2) + k. Simplifying the equation, we get y=ax2βˆ’2ahx+ah2+ky = ax^2 - 2ahx + ah^2 + k. Comparing this equation with the standard form of the quadratic function, we can see that the coefficient of the linear term is βˆ’2ah-2ah. Since the coefficient of the linear term in the standard form is bb, we can set up the equation βˆ’2ah=b-2ah = b. Solving for hh, we get h=βˆ’b2ah = \frac{-b}{2a}.

The Importance of Correctly Identifying the Value of hh

Correctly identifying the value of hh is crucial in converting a quadratic function from the standard form to the vertex form. If Shaikh incorrectly calculates the value of hh, she will end up with a quadratic function that is not equivalent to the original function. This can lead to incorrect solutions and conclusions in problems related to optimization, physics, and engineering.

Conclusion

Q: What is the standard form of a quadratic function?

A: The standard form of a quadratic function is given by the equation y=ax2+bx+cy = ax^2 + bx + c, where aa, bb, and cc are constants.

Q: What is the vertex form of a quadratic function?

A: The vertex form of a quadratic function is given by the equation y=a(xβˆ’h)2+ky = a(x - h)^2 + k, where (h,k)(h, k) is the vertex of the parabola.

Q: Why is it important to convert a quadratic function from the standard form to the vertex form?

A: Converting a quadratic function from the standard form to the vertex form is essential in mathematics, particularly in algebra and calculus. This conversion helps in analyzing the properties of the quadratic function, such as its vertex, axis of symmetry, and direction of opening.

Q: What is completing the square, and why is it necessary in converting a quadratic function from the standard form to the vertex form?

A: Completing the square is a technique used to convert a quadratic function from the standard form to the vertex form. It involves rewriting the quadratic function in a way that allows us to easily identify the vertex of the parabola. Completing the square is necessary because it helps us to correctly identify the value of hh, which is the x-coordinate of the vertex of the parabola.

Q: What is the correct value of hh in the vertex form of a quadratic function?

A: The correct value of hh is βˆ’b2a\frac{-b}{2a}. This value represents the x-coordinate of the vertex of the parabola.

Q: What is the importance of correctly identifying the value of hh in converting a quadratic function from the standard form to the vertex form?

A: Correctly identifying the value of hh is crucial in converting a quadratic function from the standard form to the vertex form. If the value of hh is incorrectly calculated, the two functions will not be equivalent, leading to incorrect solutions and conclusions in problems related to optimization, physics, and engineering.

Q: What are some common mistakes to avoid when converting a quadratic function from the standard form to the vertex form?

A: Some common mistakes to avoid when converting a quadratic function from the standard form to the vertex form include:

  • Incorrectly calculating the value of hh
  • Not completing the square correctly
  • Not simplifying the equation correctly
  • Not checking for equivalent functions

Q: How can I practice converting quadratic functions from the standard form to the vertex form?

A: You can practice converting quadratic functions from the standard form to the vertex form by:

  • Working through examples and exercises in your textbook or online resources
  • Using online calculators or software to help you with the conversion
  • Creating your own examples and exercises to practice the conversion
  • Asking your teacher or tutor for help and guidance

Q: What are some real-world applications of converting quadratic functions from the standard form to the vertex form?

A: Some real-world applications of converting quadratic functions from the standard form to the vertex form include:

  • Optimization problems in physics and engineering
  • Modeling population growth and decline in biology
  • Analyzing the motion of objects in physics
  • Solving problems related to finance and economics

Conclusion

Converting a quadratic function from the standard form to the vertex form is an essential skill in mathematics. By understanding the standard and vertex forms of quadratic functions, completing the square, and correctly identifying the value of hh, you can ensure that the two functions are equivalent and that you obtain accurate solutions and conclusions in problems related to optimization, physics, and engineering.