x^3-6*x+2=0 la ecuación
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Solución
Teorema de Cardano-Vieta
es ecuación cúbica reducida
px2+qx+v+x3=0donde
p=abp=0q=acq=−6v=adv=2Fórmulas de Cardano-Vieta
x1+x2+x3=−px1x2+x1x3+x2x3=qx1x2x3=vx1+x2+x3=0x1x2+x1x3+x2x3=−6x1x2x3=2
/ / / ___\\ / / ___\\\ / / ___\\ / / ___\\
| ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|| ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|
| \/ 2 *sin|-----------| \/ 6 *cos|-----------|| \/ 2 *cos|-----------| \/ 6 *sin|-----------|
/ 1 \ | / 1 \ \ 3 / \ 3 /| \ 3 / \ 3 /
x1 = - 6*re|------------------------------------| + I*|- 6*im|------------------------------------| + ---------------------- + ----------------------| + ---------------------- - ----------------------
| _________________ / ___\| | | _________________ / ___\| 2 2 | 2 2
|3 / ___ | 1 I*\/ 3 || | |3 / ___ | 1 I*\/ 3 || |
|\/ 27 + 27*I*\/ 7 *|- - - -------|| | |\/ 27 + 27*I*\/ 7 *|- - - -------|| |
\ \ 2 2 // \ \ \ 2 2 // /
x1=−26sin(3atan(7))−6re(−21−23i)327+277i1+22cos(3atan(7))+i−6im(−21−23i)327+277i1+22sin(3atan(7))+26cos(3atan(7))
/ / / ___\\ / / ___\\\ / / ___\\ / / ___\\
| ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|| ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|
| \/ 2 *sin|-----------| \/ 6 *cos|-----------|| \/ 2 *cos|-----------| \/ 6 *sin|-----------|
/ 1 \ | / 1 \ \ 3 / \ 3 /| \ 3 / \ 3 /
x2 = - 6*re|------------------------------------| + I*|- 6*im|------------------------------------| + ---------------------- - ----------------------| + ---------------------- + ----------------------
| _________________ / ___\| | | _________________ / ___\| 2 2 | 2 2
|3 / ___ | 1 I*\/ 3 || | |3 / ___ | 1 I*\/ 3 || |
|\/ 27 + 27*I*\/ 7 *|- - + -------|| | |\/ 27 + 27*I*\/ 7 *|- - + -------|| |
\ \ 2 2 // \ \ \ 2 2 // /
x2=26sin(3atan(7))+22cos(3atan(7))−6re(−21+23i)327+277i1+i−26cos(3atan(7))+22sin(3atan(7))−6im(−21+23i)327+277i1
_________________
3 / ___
6 \/ 27 + 27*I*\/ 7
x3 = - -------------------- - --------------------
_________________ 3
3 / ___
\/ 27 + 27*I*\/ 7
x3=−3327+277i−327+277i6
x3 = -(27 + 27*sqrt(7)*i)^(1/3)/3 - 6/(27 + 27*sqrt(7)*i)^(1/3)
Suma y producto de raíces
[src]
/ / / ___\\ / / ___\\\ / / ___\\ / / ___\\ / / / ___\\ / / ___\\\ / / ___\\ / / ___\\
| ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|| ___ |atan\\/ 7 /| ___ |atan\\/ 7 /| | ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|| ___ |atan\\/ 7 /| ___ |atan\\/ 7 /| _________________
| \/ 2 *sin|-----------| \/ 6 *cos|-----------|| \/ 2 *cos|-----------| \/ 6 *sin|-----------| | \/ 2 *sin|-----------| \/ 6 *cos|-----------|| \/ 2 *cos|-----------| \/ 6 *sin|-----------| 3 / ___
/ 1 \ | / 1 \ \ 3 / \ 3 /| \ 3 / \ 3 / / 1 \ | / 1 \ \ 3 / \ 3 /| \ 3 / \ 3 / 6 \/ 27 + 27*I*\/ 7
- 6*re|------------------------------------| + I*|- 6*im|------------------------------------| + ---------------------- + ----------------------| + ---------------------- - ---------------------- + - 6*re|------------------------------------| + I*|- 6*im|------------------------------------| + ---------------------- - ----------------------| + ---------------------- + ---------------------- + - -------------------- - --------------------
| _________________ / ___\| | | _________________ / ___\| 2 2 | 2 2 | _________________ / ___\| | | _________________ / ___\| 2 2 | 2 2 _________________ 3
|3 / ___ | 1 I*\/ 3 || | |3 / ___ | 1 I*\/ 3 || | |3 / ___ | 1 I*\/ 3 || | |3 / ___ | 1 I*\/ 3 || | 3 / ___
|\/ 27 + 27*I*\/ 7 *|- - - -------|| | |\/ 27 + 27*I*\/ 7 *|- - - -------|| | |\/ 27 + 27*I*\/ 7 *|- - + -------|| | |\/ 27 + 27*I*\/ 7 *|- - + -------|| | \/ 27 + 27*I*\/ 7
\ \ 2 2 // \ \ \ 2 2 // / \ \ 2 2 // \ \ \ 2 2 // /
26sin(3atan(7))+22cos(3atan(7))−6re(−21+23i)327+277i1+i−26cos(3atan(7))+22sin(3atan(7))−6im(−21+23i)327+277i1+−26sin(3atan(7))−6re(−21−23i)327+277i1+22cos(3atan(7))+i−6im(−21−23i)327+277i1+22sin(3atan(7))+26cos(3atan(7))+(−3327+277i−327+277i6)
/ / / ___\\ / / ___\\\ / / / ___\\ / / ___\\\
_________________ | ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|| | ___ |atan\\/ 7 /| ___ |atan\\/ 7 /||
3 / ___ | \/ 2 *sin|-----------| \/ 6 *cos|-----------|| | \/ 2 *sin|-----------| \/ 6 *cos|-----------|| / / ___\\
6 / 1 \ / 1 \ \/ 27 + 27*I*\/ 7 | / 1 \ \ 3 / \ 3 /| | / 1 \ \ 3 / \ 3 /| ___ |atan\\/ 7 /|
- -------------------- - 6*re|------------------------------------| - 6*re|------------------------------------| - -------------------- + I*|- 6*im|------------------------------------| + ---------------------- - ----------------------| + I*|- 6*im|------------------------------------| + ---------------------- + ----------------------| + \/ 2 *cos|-----------|
_________________ | _________________ / ___\| | _________________ / ___\| 3 | | _________________ / ___\| 2 2 | | | _________________ / ___\| 2 2 | \ 3 /
3 / ___ |3 / ___ | 1 I*\/ 3 || |3 / ___ | 1 I*\/ 3 || | |3 / ___ | 1 I*\/ 3 || | | |3 / ___ | 1 I*\/ 3 || |
\/ 27 + 27*I*\/ 7 |\/ 27 + 27*I*\/ 7 *|- - + -------|| |\/ 27 + 27*I*\/ 7 *|- - - -------|| | |\/ 27 + 27*I*\/ 7 *|- - + -------|| | | |\/ 27 + 27*I*\/ 7 *|- - - -------|| |
\ \ 2 2 // \ \ 2 2 // \ \ \ 2 2 // / \ \ \ 2 2 // /
−6re(−21−23i)327+277i1−6re(−21+23i)327+277i1+2cos(3atan(7))−3327+277i+i−6im(−21−23i)327+277i1+22sin(3atan(7))+26cos(3atan(7))+i−26cos(3atan(7))+22sin(3atan(7))−6im(−21+23i)327+277i1−327+277i6
/ / / / ___\\ / / ___\\\ / / ___\\ / / ___\\\ / / / / ___\\ / / ___\\\ / / ___\\ / / ___\\\
| | ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|| ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|| | | ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|| ___ |atan\\/ 7 /| ___ |atan\\/ 7 /|| / _________________\
| | \/ 2 *sin|-----------| \/ 6 *cos|-----------|| \/ 2 *cos|-----------| \/ 6 *sin|-----------|| | | \/ 2 *sin|-----------| \/ 6 *cos|-----------|| \/ 2 *cos|-----------| \/ 6 *sin|-----------|| | 3 / ___ |
| / 1 \ | / 1 \ \ 3 / \ 3 /| \ 3 / \ 3 /| | / 1 \ | / 1 \ \ 3 / \ 3 /| \ 3 / \ 3 /| | 6 \/ 27 + 27*I*\/ 7 |
|- 6*re|------------------------------------| + I*|- 6*im|------------------------------------| + ---------------------- + ----------------------| + ---------------------- - ----------------------|*|- 6*re|------------------------------------| + I*|- 6*im|------------------------------------| + ---------------------- - ----------------------| + ---------------------- + ----------------------|*|- -------------------- - --------------------|
| | _________________ / ___\| | | _________________ / ___\| 2 2 | 2 2 | | | _________________ / ___\| | | _________________ / ___\| 2 2 | 2 2 | | _________________ 3 |
| |3 / ___ | 1 I*\/ 3 || | |3 / ___ | 1 I*\/ 3 || | | | |3 / ___ | 1 I*\/ 3 || | |3 / ___ | 1 I*\/ 3 || | | | 3 / ___ |
| |\/ 27 + 27*I*\/ 7 *|- - - -------|| | |\/ 27 + 27*I*\/ 7 *|- - - -------|| | | | |\/ 27 + 27*I*\/ 7 *|- - + -------|| | |\/ 27 + 27*I*\/ 7 *|- - + -------|| | | \ \/ 27 + 27*I*\/ 7 /
\ \ \ 2 2 // \ \ \ 2 2 // / / \ \ \ 2 2 // \ \ \ 2 2 // / /
−26sin(3atan(7))−6re(−21−23i)327+277i1+22cos(3atan(7))+i−6im(−21−23i)327+277i1+22sin(3atan(7))+26cos(3atan(7))26sin(3atan(7))+22cos(3atan(7))−6re(−21+23i)327+277i1+i−26cos(3atan(7))+22sin(3atan(7))−6im(−21+23i)327+277i1(−3327+277i−327+277i6)
/ / / ___\\\ / 2/3\
| |2*atan\\/ 7 /|| | / ___\ |
2*|1 - 2*cos|-------------||*\2 + \1 + I*\/ 7 / /
\ \ 3 //
---------------------------------------------------
_____________
3 / ___
\/ 1 + I*\/ 7
31+7i2(1−2cos(32atan(7)))(2+(1+7i)32)
2*(1 - 2*cos(2*atan(sqrt(7))/3))*(2 + (1 + i*sqrt(7))^(2/3))/(1 + i*sqrt(7))^(1/3)