Solución detallada
Es la ecuación de la forma
a*x^2 + b*x + c = 0
La ecuación cuadrática puede ser resuelta
con la ayuda del discriminante.
Las raíces de la ecuación cuadrática:
$$x_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{2} = \frac{- \sqrt{D} - b}{2 a}$$
donde D = b^2 - 4*a*c es el discriminante.
Como
$$a = 1$$
$$b = k$$
$$c = -16$$
, entonces
D = b^2 - 4 * a * c =
(k)^2 - 4 * (1) * (-16) = 64 + k^2
La ecuación tiene dos raíces.
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
o
$$x_{1} = - \frac{k}{2} + \frac{\sqrt{k^{2} + 64}}{2}$$
$$x_{2} = - \frac{k}{2} - \frac{\sqrt{k^{2} + 64}}{2}$$
/ ___________________________________________ \ ___________________________________________
| / 2 / / 2 2 \\| / 2 / / 2 2 \\
| 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|| 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|
| \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *sin|------------------------------------------|| \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *cos|------------------------------------------|
re(k) | im(k) \ 2 /| \ 2 /
x1 = - ----- + I*|- ----- - -----------------------------------------------------------------------------------------------| - -----------------------------------------------------------------------------------------------
2 \ 2 2 / 2
$$x_{1} = i \left(- \frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{im}{\left(k\right)}}{2}\right) - \frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{re}{\left(k\right)}}{2}$$
/ ___________________________________________ \ ___________________________________________
| / 2 / / 2 2 \\| / 2 / / 2 2 \\
| 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|| 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|
| \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *sin|------------------------------------------|| \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *cos|------------------------------------------|
re(k) | im(k) \ 2 /| \ 2 /
x2 = - ----- + I*|- ----- + -----------------------------------------------------------------------------------------------| + -----------------------------------------------------------------------------------------------
2 \ 2 2 / 2
$$x_{2} = i \left(\frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{im}{\left(k\right)}}{2}\right) + \frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{re}{\left(k\right)}}{2}$$
x2 = i*(((re(k)^2 - im(k)^2 + 64)^2 + 4*re(k)^2*im(k)^2)^(1/4)*sin(atan2(2*re(k)*im(k, re(k)^2 - im(k)^2 + 64)/2)/2 - im(k)/2) + ((re(k)^2 - im(k)^2 + 64)^2 + 4*re(k)^2*im(k)^2)^(1/4)*cos(atan2(2*re(k)*im(k), re(k)^2 - im(k)^2 + 64)/2)/2 - re(k)/2)
Suma y producto de raíces
[src]
/ ___________________________________________ \ ___________________________________________ / ___________________________________________ \ ___________________________________________
| / 2 / / 2 2 \\| / 2 / / 2 2 \\ | / 2 / / 2 2 \\| / 2 / / 2 2 \\
| 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|| 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/| | 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|| 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|
| \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *sin|------------------------------------------|| \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *cos|------------------------------------------| | \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *sin|------------------------------------------|| \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *cos|------------------------------------------|
re(k) | im(k) \ 2 /| \ 2 / re(k) | im(k) \ 2 /| \ 2 /
- ----- + I*|- ----- - -----------------------------------------------------------------------------------------------| - ----------------------------------------------------------------------------------------------- + - ----- + I*|- ----- + -----------------------------------------------------------------------------------------------| + -----------------------------------------------------------------------------------------------
2 \ 2 2 / 2 2 \ 2 2 / 2
$$\left(i \left(- \frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{im}{\left(k\right)}}{2}\right) - \frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{re}{\left(k\right)}}{2}\right) + \left(i \left(\frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{im}{\left(k\right)}}{2}\right) + \frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{re}{\left(k\right)}}{2}\right)$$
/ ___________________________________________ \ / ___________________________________________ \
| / 2 / / 2 2 \\| | / 2 / / 2 2 \\|
| 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|| | 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/||
| \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *sin|------------------------------------------|| | \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *sin|------------------------------------------||
| im(k) \ 2 /| | im(k) \ 2 /|
-re(k) + I*|- ----- + -----------------------------------------------------------------------------------------------| + I*|- ----- - -----------------------------------------------------------------------------------------------|
\ 2 2 / \ 2 2 /
$$i \left(- \frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{im}{\left(k\right)}}{2}\right) + i \left(\frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{im}{\left(k\right)}}{2}\right) - \operatorname{re}{\left(k\right)}$$
/ / ___________________________________________ \ ___________________________________________ \ / / ___________________________________________ \ ___________________________________________ \
| | / 2 / / 2 2 \\| / 2 / / 2 2 \\| | | / 2 / / 2 2 \\| / 2 / / 2 2 \\|
| | 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|| 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|| | | 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/|| 4 / / 2 2 \ 2 2 |atan2\2*im(k)*re(k), 64 + re (k) - im (k)/||
| | \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *sin|------------------------------------------|| \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *cos|------------------------------------------|| | | \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *sin|------------------------------------------|| \/ \64 + re (k) - im (k)/ + 4*im (k)*re (k) *cos|------------------------------------------||
| re(k) | im(k) \ 2 /| \ 2 /| | re(k) | im(k) \ 2 /| \ 2 /|
|- ----- + I*|- ----- - -----------------------------------------------------------------------------------------------| - -----------------------------------------------------------------------------------------------|*|- ----- + I*|- ----- + -----------------------------------------------------------------------------------------------| + -----------------------------------------------------------------------------------------------|
\ 2 \ 2 2 / 2 / \ 2 \ 2 2 / 2 /
$$\left(i \left(- \frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{im}{\left(k\right)}}{2}\right) - \frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{re}{\left(k\right)}}{2}\right) \left(i \left(\frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{im}{\left(k\right)}}{2}\right) + \frac{\sqrt[4]{\left(\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64\right)^{2} + 4 \left(\operatorname{re}{\left(k\right)}\right)^{2} \left(\operatorname{im}{\left(k\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(k\right)} \operatorname{im}{\left(k\right)},\left(\operatorname{re}{\left(k\right)}\right)^{2} - \left(\operatorname{im}{\left(k\right)}\right)^{2} + 64 \right)}}{2} \right)}}{2} - \frac{\operatorname{re}{\left(k\right)}}{2}\right)$$
$$-16$$