Mister Exam

|(x+1)3|=X3 equation

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Numerical solution:

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The solution

You have entered [src]
|(x + 1)*3| = x3
$$\left|{3 \left(x + 1\right)}\right| = x_{3}$$
Detail solution
For every modulo expressions in the equation
allow cases, when this expressions ">=0" or "<0",
solve the resulting equation.

1.
$$3 x + 3 \geq 0$$
or
$$-1 \leq x \wedge x < \infty$$
we get the equation
$$- x_{3} + \left(3 x + 3\right) = 0$$
after simplifying we get
$$3 x - x_{3} + 3 = 0$$
the solution in this interval:
$$x_{1} = \frac{x_{3}}{3} - 1$$

2.
$$3 x + 3 < 0$$
or
$$-\infty < x \wedge x < -1$$
we get the equation
$$- x_{3} + \left(- 3 x - 3\right) = 0$$
after simplifying we get
$$- 3 x - x_{3} - 3 = 0$$
the solution in this interval:
$$x_{2} = - \frac{x_{3}}{3} - 1$$


The final answer:
$$x_{1} = \frac{x_{3}}{3} - 1$$
$$x_{2} = - \frac{x_{3}}{3} - 1$$
The graph
Rapid solution [src]
         //     x3            \     //     x3            \
         ||-1 - --  for x3 > 0|     ||-1 - --  for x3 > 0|
x1 = I*im|<     3             | + re|<     3             |
         ||                   |     ||                   |
         \\  nan    otherwise /     \\  nan    otherwise /
$$x_{1} = \operatorname{re}{\left(\begin{cases} - \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} > 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)} + i \operatorname{im}{\left(\begin{cases} - \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} > 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)}$$
         //     x3             \     //     x3             \
         ||-1 + --  for x3 >= 0|     ||-1 + --  for x3 >= 0|
x2 = I*im|<     3              | + re|<     3              |
         ||                    |     ||                    |
         \\  nan     otherwise /     \\  nan     otherwise /
$$x_{2} = \operatorname{re}{\left(\begin{cases} \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} \geq 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)} + i \operatorname{im}{\left(\begin{cases} \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} \geq 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)}$$
Eq(x2, re(Piecewise((x3/3 - 1, x3 >= 0), (nan, True))) + i*im(Piecewise((x3/3 - 1, x3 >= 0), (nan, True))))
Sum and product of roots [src]
sum
    //     x3            \     //     x3            \       //     x3             \     //     x3             \
    ||-1 - --  for x3 > 0|     ||-1 - --  for x3 > 0|       ||-1 + --  for x3 >= 0|     ||-1 + --  for x3 >= 0|
I*im|<     3             | + re|<     3             | + I*im|<     3              | + re|<     3              |
    ||                   |     ||                   |       ||                    |     ||                    |
    \\  nan    otherwise /     \\  nan    otherwise /       \\  nan     otherwise /     \\  nan     otherwise /
$$\left(\operatorname{re}{\left(\begin{cases} - \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} > 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)} + i \operatorname{im}{\left(\begin{cases} - \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} > 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)}\right) + \left(\operatorname{re}{\left(\begin{cases} \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} \geq 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)} + i \operatorname{im}{\left(\begin{cases} \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} \geq 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)}\right)$$
=
    //     x3            \       //     x3             \     //     x3            \     //     x3             \
    ||-1 - --  for x3 > 0|       ||-1 + --  for x3 >= 0|     ||-1 - --  for x3 > 0|     ||-1 + --  for x3 >= 0|
I*im|<     3             | + I*im|<     3              | + re|<     3             | + re|<     3              |
    ||                   |       ||                    |     ||                   |     ||                    |
    \\  nan    otherwise /       \\  nan     otherwise /     \\  nan    otherwise /     \\  nan     otherwise /
$$\operatorname{re}{\left(\begin{cases} - \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} > 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)} + \operatorname{re}{\left(\begin{cases} \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} \geq 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)} + i \operatorname{im}{\left(\begin{cases} - \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} > 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)} + i \operatorname{im}{\left(\begin{cases} \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} \geq 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)}$$
product
/    //     x3            \     //     x3            \\ /    //     x3             \     //     x3             \\
|    ||-1 - --  for x3 > 0|     ||-1 - --  for x3 > 0|| |    ||-1 + --  for x3 >= 0|     ||-1 + --  for x3 >= 0||
|I*im|<     3             | + re|<     3             ||*|I*im|<     3              | + re|<     3              ||
|    ||                   |     ||                   || |    ||                    |     ||                    ||
\    \\  nan    otherwise /     \\  nan    otherwise // \    \\  nan     otherwise /     \\  nan     otherwise //
$$\left(\operatorname{re}{\left(\begin{cases} - \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} > 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)} + i \operatorname{im}{\left(\begin{cases} - \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} > 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)}\right) \left(\operatorname{re}{\left(\begin{cases} \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} \geq 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)} + i \operatorname{im}{\left(\begin{cases} \frac{x_{3}}{3} - 1 & \text{for}\: x_{3} \geq 0 \\\text{NaN} & \text{otherwise} \end{cases}\right)}\right)$$
=
/-(-3 + I*im(x3) + re(x3))*(3 + I*im(x3) + re(x3))             
|--------------------------------------------------  for x3 > 0
<                        9                                     
|                                                              
\                       nan                          otherwise 
$$\begin{cases} - \frac{\left(\operatorname{re}{\left(x_{3}\right)} + i \operatorname{im}{\left(x_{3}\right)} - 3\right) \left(\operatorname{re}{\left(x_{3}\right)} + i \operatorname{im}{\left(x_{3}\right)} + 3\right)}{9} & \text{for}\: x_{3} > 0 \\\text{NaN} & \text{otherwise} \end{cases}$$
Piecewise((-(-3 + i*im(x3) + re(x3))*(3 + i*im(x3) + re(x3))/9, x3 > 0), (nan, True))