- Data Structure
- Networking
- RDBMS
- Operating System
- Java
- MS Excel
- iOS
- HTML
- CSS
- Android
- Python
- C Programming
- C++
- C#
- MongoDB
- MySQL
- Javascript
- PHP
- Physics
- Chemistry
- Biology
- Mathematics
- English
- Economics
- Psychology
- Social Studies
- Fashion Studies
- Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Find the roots of the following quadratic equation:
$x^{2} -3\sqrt {5}\ x+10=0$
Given: The expression: $x^{2} -3\sqrt{5} \ x+10=0$
To do: To find the roots of the given quadratic equation.
Solution: We know that for a quadratic equation $ax^{2} +bx+c=0$
$x=\frac{-b\pm \sqrt{b^{2} -4ac}}{2a}$
On comparing it to the given quadratic equation $a=1,b=-3\sqrt{5} \ and\ c=10$
On substituting these values of $\displaystyle a,\ b\ and\ c$
$x=\frac{-( -3\surd 5) \pm \sqrt{( -3\surd 5)^{2} -4\times 1\times 10}}{2\times 1}$
$x=\frac{3\sqrt{5} \pm \sqrt{( 45-40)}}{2}$
$x=\frac{\left( 3\sqrt{5} \pm \sqrt{5}\right)}{2}$
If $x=\frac{\left( 3\sqrt{5} +\sqrt{5}\right)}{2}$
$\Rightarrow x=\frac{4\sqrt{5}}{2} $
$\Rightarrow x=2\sqrt{5}$
If $x=\frac{\left( 3\sqrt{5} -\sqrt{5}\right)}{2}$
$\Rightarrow x=\frac{\left( 2\sqrt{5}\right)}{2}$
$\Rightarrow x=\sqrt{5}$
$\therefore x=2\sqrt{5}, \ \sqrt{5}$
Advertisements