Mister Exam

Other calculators

4(x+1)(x+2)(x+3)(x+6)=-3x^2 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
4*(x + 1)*(x + 2)*(x + 3)*(x + 6) = -3*x 
$$4 \left(x + 1\right) \left(x + 2\right) \left(x + 3\right) \left(x + 6\right) = - 3 x^{2}$$
Detail solution
Given the equation:
$$4 \left(x + 1\right) \left(x + 2\right) \left(x + 3\right) \left(x + 6\right) = - 3 x^{2}$$
transform:
Take common factor from the equation
$$\left(x + 4\right) \left(2 x + 3\right) \left(2 x^{2} + 13 x + 12\right) = 0$$
Because the right side of the equation is zero, then the solution of the equation is exists if at least one of the multipliers in the left side of the equation equal to zero.
We get the equations
$$x + 4 = 0$$
$$2 x + 3 = 0$$
$$2 x^{2} + 13 x + 12 = 0$$
solve the resulting equation:
1.
$$x + 4 = 0$$
Move free summands (without x)
from left part to right part, we given:
$$x = -4$$
We get the answer: x1 = -4
2.
$$2 x + 3 = 0$$
Move free summands (without x)
from left part to right part, we given:
$$2 x = -3$$
Divide both parts of the equation by 2
x = -3 / (2)

We get the answer: x2 = -3/2
3.
$$2 x^{2} + 13 x + 12 = 0$$
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:
$$x_{3} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{4} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 2$$
$$b = 13$$
$$c = 12$$
, then
D = b^2 - 4 * a * c = 

(13)^2 - 4 * (2) * (12) = 73

Because D > 0, then the equation has two roots.
x3 = (-b + sqrt(D)) / (2*a)

x4 = (-b - sqrt(D)) / (2*a)

or
$$x_{3} = - \frac{13}{4} + \frac{\sqrt{73}}{4}$$
$$x_{4} = - \frac{13}{4} - \frac{\sqrt{73}}{4}$$
The final answer:
$$x_{1} = -4$$
$$x_{2} = - \frac{3}{2}$$
$$x_{3} = - \frac{13}{4} + \frac{\sqrt{73}}{4}$$
$$x_{4} = - \frac{13}{4} - \frac{\sqrt{73}}{4}$$
The graph
Rapid solution [src]
x1 = -4
$$x_{1} = -4$$
x2 = -3/2
$$x_{2} = - \frac{3}{2}$$
              ____
       13   \/ 73 
x3 = - -- - ------
       4      4   
$$x_{3} = - \frac{13}{4} - \frac{\sqrt{73}}{4}$$
              ____
       13   \/ 73 
x4 = - -- + ------
       4      4   
$$x_{4} = - \frac{13}{4} + \frac{\sqrt{73}}{4}$$
x4 = -13/4 + sqrt(73)/4
Sum and product of roots [src]
sum
                    ____            ____
             13   \/ 73      13   \/ 73 
-4 - 3/2 + - -- - ------ + - -- + ------
             4      4        4      4   
$$\left(\left(-4 - \frac{3}{2}\right) + \left(- \frac{13}{4} - \frac{\sqrt{73}}{4}\right)\right) + \left(- \frac{13}{4} + \frac{\sqrt{73}}{4}\right)$$
=
-12
$$-12$$
product
        /         ____\ /         ____\
-4*(-3) |  13   \/ 73 | |  13   \/ 73 |
-------*|- -- - ------|*|- -- + ------|
   2    \  4      4   / \  4      4   /
$$- -6 \left(- \frac{13}{4} - \frac{\sqrt{73}}{4}\right) \left(- \frac{13}{4} + \frac{\sqrt{73}}{4}\right)$$
=
36
$$36$$
36
Numerical answer [src]
x1 = -1.5
x2 = -4.0
x3 = -1.11399906367062
x4 = -5.38600093632938
x4 = -5.38600093632938