The Roots Of A Quadratic Equation Are Given By $x = \frac{-10 \pm \sqrt{100 - 4k^2}}{2k}$. Calculate The Values Of $k$ For Which The Roots Are:1.3.1 Equal1.3.2 Non-real---Simplify The Following Expressions Completely:2.1.1

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Introduction

In algebra, a quadratic equation is a polynomial equation of degree two, which means the highest power of the variable is two. The general form of a quadratic equation is ax2+bx+c=0ax^2 + bx + c = 0, where aa, bb, and cc are constants. The roots of a quadratic equation are the values of xx that satisfy the equation. In this article, we will explore the roots of a quadratic equation given by $x = \frac{-10 \pm \sqrt{100 - 4k^2}}{2k}$ and calculate the values of kk for which the roots are equal and non-real.

Equal Roots

To find the values of kk for which the roots are equal, we need to set the two roots equal to each other and solve for kk. The two roots are given by $x_1 = \frac{-10 + \sqrt{100 - 4k^2}}{2k}$ and $x_2 = \frac{-10 - \sqrt{100 - 4k^2}}{2k}$.

Setting the two roots equal to each other, we get:

−10+100−4k22k=−10−100−4k22k\frac{-10 + \sqrt{100 - 4k^2}}{2k} = \frac{-10 - \sqrt{100 - 4k^2}}{2k}

Simplifying the equation, we get:

100−4k2=0\sqrt{100 - 4k^2} = 0

Squaring both sides of the equation, we get:

100−4k2=0100 - 4k^2 = 0

Solving for kk, we get:

4k2=1004k^2 = 100

k2=25k^2 = 25

k=±5k = \pm 5

Therefore, the values of kk for which the roots are equal are k=5k = 5 and k=−5k = -5.

Non-Real Roots

To find the values of kk for which the roots are non-real, we need to ensure that the discriminant 100−4k2100 - 4k^2 is negative. The discriminant is given by:

100−4k2<0100 - 4k^2 < 0

Simplifying the inequality, we get:

4k2>1004k^2 > 100

Dividing both sides of the inequality by 4, we get:

k2>25k^2 > 25

Taking the square root of both sides of the inequality, we get:

k>5k > 5

or

k<−5k < -5

Therefore, the values of kk for which the roots are non-real are k>5k > 5 and k<−5k < -5.

Simplifying Expressions

2.1.1 Simplify the following expressions completely:

12+1\frac{1}{\sqrt{2} + 1}

To simplify the expression, we can multiply the numerator and denominator by the conjugate of the denominator:

12+1⋅2−12−1\frac{1}{\sqrt{2} + 1} \cdot \frac{\sqrt{2} - 1}{\sqrt{2} - 1}

Simplifying the expression, we get:

2−1(2+1)(2−1)\frac{\sqrt{2} - 1}{(\sqrt{2} + 1)(\sqrt{2} - 1)}

Simplifying the denominator, we get:

2−12−1\frac{\sqrt{2} - 1}{2 - 1}

Simplifying the expression, we get:

2−1\sqrt{2} - 1

Therefore, the simplified expression is 2−1\sqrt{2} - 1.

Conclusion

Introduction

In our previous article, we explored the roots of a quadratic equation given by $x = \frac{-10 \pm \sqrt{100 - 4k^2}}{2k}$ and calculated the values of kk for which the roots are equal and non-real. In this article, we will answer some frequently asked questions related to the roots of a quadratic equation.

Q&A

Q: What is the general form of a quadratic equation?

A: The general form of a quadratic equation is ax2+bx+c=0ax^2 + bx + c = 0, where aa, bb, and cc are constants.

Q: What are the roots of a quadratic equation?

A: The roots of a quadratic equation are the values of xx that satisfy the equation.

Q: How do you find the values of kk for which the roots are equal?

A: To find the values of kk for which the roots are equal, you need to set the two roots equal to each other and solve for kk.

Q: How do you find the values of kk for which the roots are non-real?

A: To find the values of kk for which the roots are non-real, you need to ensure that the discriminant 100−4k2100 - 4k^2 is negative.

Q: What is the discriminant of a quadratic equation?

A: The discriminant of a quadratic equation is the expression under the square root in the quadratic formula, which is b2−4acb^2 - 4ac.

Q: How do you simplify the expression 12+1\frac{1}{\sqrt{2} + 1}?

A: To simplify the expression 12+1\frac{1}{\sqrt{2} + 1}, you can multiply the numerator and denominator by the conjugate of the denominator, which is 2−1\sqrt{2} - 1.

Q: What is the simplified form of the expression 12+1\frac{1}{\sqrt{2} + 1}?

A: The simplified form of the expression 12+1\frac{1}{\sqrt{2} + 1} is 2−1\sqrt{2} - 1.

Q: What are the values of kk for which the roots are equal?

A: The values of kk for which the roots are equal are k=5k = 5 and k=−5k = -5.

Q: What are the values of kk for which the roots are non-real?

A: The values of kk for which the roots are non-real are k>5k > 5 and k<−5k < -5.

Conclusion

In conclusion, we have answered some frequently asked questions related to the roots of a quadratic equation. We have also provided the general form of a quadratic equation, the definition of the roots of a quadratic equation, and the values of kk for which the roots are equal and non-real. We hope that this article has been helpful in clarifying any doubts you may have had about the roots of a quadratic equation.

Additional Resources

Final Thoughts

We hope that this article has been helpful in providing a comprehensive overview of the roots of a quadratic equation. If you have any further questions or need additional clarification, please don't hesitate to ask.