Finding the Perfect Square for a Quadratic Equation

Introduction to Quadratic Equations and Perfect Squares

Quadratic equations, expressions of the form ax^2 bx c 0, where a, b, and c are constants, are widely studied in mathematics. Among these, equations that can be transformed into perfect squares (of the form (px q)^2 0) exhibit special properties. In this article, we explore how to determine the value of k for which the given quadratic equation is a perfect square.

Determining the Conditions for a Perfect Square

A quadratic equation can be a perfect square if its discriminant (D) is equal to zero. The discriminant is given by the formula (D b^2 - 4ac). For a quadratic equation of the form (4 - kx^2 2k4x 8k1 0) to be a perfect square, its discriminant must be zero. Let's go through the steps to find the value of k that satisfies this condition.

Step 1: Setting up the Equation

The given equation is (4 - kx^2 2k4x 8k1 0). To find the value of k for which this equation is a perfect square, we equate the discriminant to zero:

#34;b^2 - 4ac  0#34;

Here, (a 4 - k), (b 2k4), and (c 8k1).

Step 2: Substituting the Values

Substituting these values into the discriminant formula, we get:

[ (2k4)^2 - 4(4 - k)(8k1)  0 ]

Simplifying this equation:

[ 4k4^2 - 4(4 - k)(8k1)  0 ]

Further simplification:

[ 4k4^2 - 16(4 - k)(2k1)  0 ]

This can be rewritten as:

[ 4(k4)^2 - 4(32k - 16   2k^2 - k)  0 ]

Further simplification leads to:

[ 36k^2 - 108k  0 ]

Step 3: Solving the Equation

We can factorize the above equation as follows:

[ 36k(k - 3)  0 ]

This gives us two solutions:

[ k  0 quad text{or} quad k  3 ]

Thus, the values of k that make the given quadratic equation a perfect square are (k 0) and (k 3).

Step 4: Verifying the Solutions

Let's verify these solutions by substituting them back into the original equation.

For (k 0):The equation becomes (4x^2 0 - 8 0), which simplifies to (4x^2 8), or (x^2 2), which is not a perfect (k 3):The equation becomes (4 - 3x^2 24x 24 0), or (-3x^2 24x 24 0). This can be rearranged as ((x - 5)^2 0), which is a perfect square.

Therefore, the value of k that makes the given quadratic equation a perfect square is (k 3).

Conclusion

To summarize, in order for the quadratic equation (4 - kx^2 2k4x 8k1 0) to be a perfect square, the value of k must be 3. This is a key concept in the study of quadratic equations and is crucial for understanding more complex mathematical problems.

Further Reading

Quadratic Equations on WikipediaSolving Quadratic Equations by Lamar University