Question

What is quadratic formula and why it is used in maths? Hlp me fast!!

Answer 1

Hey there!!
ax2 + bx + c = 0 is a quadratic equation in the variable x. Here a, b, c are real numbers and a ≠ 0

If α is the root of quadratic equation ax2 + bx + c = 0

For a given quadratic equation, ax2 + bx + c = 0; the roots can be given by (see image)..
It is used to determine roots of a quadratic equation.

Answer 2

Heya!!

Here is your solution:-
____________________________________
Quadratic formulae is:
$x = \frac{ - b \frac{ + }{} \sqrt{ {b}^{2} - 4ac } }{2a}$
Quadratic formulae is used to find the roots of an quadratic equation or solution of an quadratic equation.

For example:-

Consider,

${x}^{2} + 2x - 1 = 0$
Comparing the above equation with general form of quadratic equation,
$a {x}^{2} + bx + c = 0$
,we get,

a=1
b=2
c=-1

Therefore,

$x = \frac{ - b \frac{ + }{} \sqrt{ {b}^{2} - 4ac} }{2a} \\ = > x = \frac{ - 2 \frac{ + }{} \sqrt{(2) ^{2} - 4.1. (- 1)} }{2.1} \\ = > x = \frac{ - 2 \frac{ + }{ } \sqrt{4 + 4} }{2} \\ = > x = \frac{ - 2 \frac{ + }{} \sqrt{8} }{2}$
Now,

$x = \frac{ - 2 + \sqrt{8} }{2} \: or \: x = \frac{ - 2 - \sqrt{8} }{2} \\ = > x = \frac{ - 2}{2} \ + \frac{ \sqrt{8} }{2} \: or \: x = \frac{ - 2}{2} - \frac{ \sqrt{8} }{2} \\ = > x = - 1 + \frac{2 \sqrt{2} }{2} \: or \: x = - 1 - \frac{2 \sqrt{2} }{2 } \\ = > x = - 1 + \sqrt{2} \: or \: x = - 1 - \sqrt{2}$

Therefore the roots of the equation are:
$x = - 1 + \sqrt{2} \: or \: - 1 - \sqrt{2}$

Hope it helps you.

Mark as Brainliest answer.