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x^4=14

x^4=14 equation

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Numerical solution:

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The solution

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 4     
x  = 14
$$x^{4} = 14$$
Detail solution
Given the equation
$$x^{4} = 14$$
Because equation degree is equal to = 4 - contains the even number 4 in the numerator, then
the equation has two real roots.
Get the root 4-th degree of the equation sides:
We get:
$$\sqrt[4]{\left(1 x + 0\right)^{4}} = \sqrt[4]{14}$$
$$\sqrt[4]{\left(1 x + 0\right)^{4}} = - \sqrt[4]{14}$$
or
$$x = \sqrt[4]{14}$$
$$x = - \sqrt[4]{14}$$
Expand brackets in the right part
x = 14^1/4

We get the answer: x = 14^(1/4)
Expand brackets in the right part
x = -14^1/4

We get the answer: x = -14^(1/4)
or
$$x_{1} = - \sqrt[4]{14}$$
$$x_{2} = \sqrt[4]{14}$$

All other 2 root(s) is the complex numbers.
do replacement:
$$z = x$$
then the equation will be the:
$$z^{4} = 14$$
Any complex number can presented so:
$$z = r e^{i p}$$
substitute to the equation
$$r^{4} e^{4 i p} = 14$$
where
$$r = \sqrt[4]{14}$$
- the magnitude of the complex number
Substitute r:
$$e^{4 i p} = 1$$
Using Euler’s formula, we find roots for p
$$i \sin{\left(4 p \right)} + \cos{\left(4 p \right)} = 1$$
so
$$\cos{\left(4 p \right)} = 1$$
and
$$\sin{\left(4 p \right)} = 0$$
then
$$p = \frac{\pi N}{2}$$
where N=0,1,2,3,...
Looping through the values of N and substituting p into the formula for z
Consequently, the solution will be for z:
$$z_{1} = - \sqrt[4]{14}$$
$$z_{2} = \sqrt[4]{14}$$
$$z_{3} = - \sqrt[4]{14} i$$
$$z_{4} = \sqrt[4]{14} i$$
do backward replacement
$$z = x$$
$$x = z$$

The final answer:
$$x_{1} = - \sqrt[4]{14}$$
$$x_{2} = \sqrt[4]{14}$$
$$x_{3} = - \sqrt[4]{14} i$$
$$x_{4} = \sqrt[4]{14} i$$
The graph
Sum and product of roots [src]
sum
    4 ____   4 ____     4 ____     4 ____
0 - \/ 14  + \/ 14  - I*\/ 14  + I*\/ 14 
$$\left(\left(\left(- \sqrt[4]{14} + 0\right) + \sqrt[4]{14}\right) - \sqrt[4]{14} i\right) + \sqrt[4]{14} i$$
=
0
$$0$$
product
   4 ____ 4 ____    4 ____   4 ____
1*-\/ 14 *\/ 14 *-I*\/ 14 *I*\/ 14 
$$\sqrt[4]{14} i - \sqrt[4]{14} i \sqrt[4]{14} \cdot 1 \left(- \sqrt[4]{14}\right)$$
=
-14
$$-14$$
-14
Rapid solution [src]
      4 ____
x1 = -\/ 14 
$$x_{1} = - \sqrt[4]{14}$$
     4 ____
x2 = \/ 14 
$$x_{2} = \sqrt[4]{14}$$
        4 ____
x3 = -I*\/ 14 
$$x_{3} = - \sqrt[4]{14} i$$
       4 ____
x4 = I*\/ 14 
$$x_{4} = \sqrt[4]{14} i$$
Numerical answer [src]
x1 = -1.93433642026767
x2 = 1.93433642026767
x3 = -1.93433642026767*i
x4 = 1.93433642026767*i
x4 = 1.93433642026767*i
The graph
x^4=14 equation