Mister Exam

Other calculators

(-8x^2-4x+2)^2=0 equation

The teacher will be very surprised to see your correct solution 😉

v

Numerical solution:

Do search numerical solution at [, ]

The solution

You have entered [src]
                  2    
/     2          \     
\- 8*x  - 4*x + 2/  = 0
$$\left(\left(- 8 x^{2} - 4 x\right) + 2\right)^{2} = 0$$
Detail solution
$$\left(\left(- 8 x^{2} - 4 x\right) + 2\right)^{2} = 0$$
transform
$$- 8 x^{2} - 4 x + 2 = 0$$
This equation is of the form
a*x^2 + b*x + c = 0

A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$x_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = -8$$
$$b = -4$$
$$c = 2$$
, then
D = b^2 - 4 * a * c = 

(-4)^2 - 4 * (-8) * (2) = 80

Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)

x2 = (-b - sqrt(D)) / (2*a)

or
$$x_{1} = - \frac{\sqrt{5}}{4} - \frac{1}{4}$$
$$x_{2} = - \frac{1}{4} + \frac{\sqrt{5}}{4}$$
The graph
Rapid solution [src]
             ___
       1   \/ 5 
x1 = - - + -----
       4     4  
$$x_{1} = - \frac{1}{4} + \frac{\sqrt{5}}{4}$$
             ___
       1   \/ 5 
x2 = - - - -----
       4     4  
$$x_{2} = - \frac{\sqrt{5}}{4} - \frac{1}{4}$$
x2 = -sqrt(5)/4 - 1/4
Sum and product of roots [src]
sum
        ___           ___
  1   \/ 5      1   \/ 5 
- - + ----- + - - - -----
  4     4       4     4  
$$\left(- \frac{\sqrt{5}}{4} - \frac{1}{4}\right) + \left(- \frac{1}{4} + \frac{\sqrt{5}}{4}\right)$$
=
-1/2
$$- \frac{1}{2}$$
product
/        ___\ /        ___\
|  1   \/ 5 | |  1   \/ 5 |
|- - + -----|*|- - - -----|
\  4     4  / \  4     4  /
$$\left(- \frac{1}{4} + \frac{\sqrt{5}}{4}\right) \left(- \frac{\sqrt{5}}{4} - \frac{1}{4}\right)$$
=
-1/4
$$- \frac{1}{4}$$
-1/4
Numerical answer [src]
x1 = -0.809016994374947
x2 = 0.309016994374947
x2 = 0.309016994374947