2^x=-4 equation
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The solution
Detail solution
Given the equation:
$$2^{x} = -4$$
or
$$2^{x} + 4 = 0$$
or
$$2^{x} = -4$$
or
$$2^{x} = -4$$
- this is the simplest exponential equation
Do replacement
$$v = 2^{x}$$
we get
$$v + 4 = 0$$
or
$$v + 4 = 0$$
Move free summands (without v)
from left part to right part, we given:
$$v = -4$$
We get the answer: v = -4
do backward replacement
$$2^{x} = v$$
or
$$x = \frac{\log{\left(v \right)}}{\log{\left(2 \right)}}$$
The final answer
$$x_{1} = \frac{\log{\left(-4 \right)}}{\log{\left(2 \right)}} = \frac{\log{\left(4 \right)} + i \pi}{\log{\left(2 \right)}}$$
Sum and product of roots
[src]
log(4) pi*I
------ + ------
log(2) log(2)
$$\frac{\log{\left(4 \right)}}{\log{\left(2 \right)}} + \frac{i \pi}{\log{\left(2 \right)}}$$
log(4) pi*I
------ + ------
log(2) log(2)
$$\frac{\log{\left(4 \right)}}{\log{\left(2 \right)}} + \frac{i \pi}{\log{\left(2 \right)}}$$
log(4) pi*I
------ + ------
log(2) log(2)
$$\frac{\log{\left(4 \right)}}{\log{\left(2 \right)}} + \frac{i \pi}{\log{\left(2 \right)}}$$
pi*I + log(4)
-------------
log(2)
$$\frac{\log{\left(4 \right)} + i \pi}{\log{\left(2 \right)}}$$
log(4) pi*I
x1 = ------ + ------
log(2) log(2)
$$x_{1} = \frac{\log{\left(4 \right)}}{\log{\left(2 \right)}} + \frac{i \pi}{\log{\left(2 \right)}}$$
x1 = log(4)/log(2) + i*pi/log(2)
x1 = 2.0 + 4.53236014182719*i
x1 = 2.0 + 4.53236014182719*i