x^3-x^2-5=0 la ecuación
El profesor se sorprenderá mucho al ver tu solución correcta😉
Solución
Teorema de Cardano-Vieta
es ecuación cúbica reducida
px2+qx+v+x3=0donde
p=abp=−1q=acq=0v=adv=−5Fórmulas de Cardano-Vieta
x1+x2+x3=−px1x2+x1x3+x2x3=qx1x2x3=vx1+x2+x3=1x1x2+x1x3+x2x3=0x1x2x3=−5
Gráfica
________________ / ________________ \
/ ______ | / ______ |
/ 137 \/ 2085 | ___ / 137 \/ 2085 |
3 / --- + -------- | \/ 3 *3 / --- + -------- ___ |
1 \/ 54 18 1 | \/ 54 18 \/ 3 |
x1 = - - --------------------- - ------------------------ + I*|- --------------------------- + ------------------------|
3 2 ________________ | 2 ________________|
/ ______ | / ______ |
/ 137 \/ 2085 | / 137 \/ 2085 |
18*3 / --- + -------- | 18*3 / --- + -------- |
\/ 54 18 \ \/ 54 18 /
x1=−23182085+54137−183182085+541371+31+i−233182085+54137+183182085+541373
________________ / ________________ \
/ ______ | / ______ |
/ 137 \/ 2085 | ___ / 137 \/ 2085 |
3 / --- + -------- |\/ 3 *3 / --- + -------- ___ |
1 \/ 54 18 1 | \/ 54 18 \/ 3 |
x2 = - - --------------------- - ------------------------ + I*|--------------------------- - ------------------------|
3 2 ________________ | 2 ________________|
/ ______ | / ______ |
/ 137 \/ 2085 | / 137 \/ 2085 |
18*3 / --- + -------- | 18*3 / --- + -------- |
\/ 54 18 \ \/ 54 18 /
x2=−23182085+54137−183182085+541371+31+i−183182085+541373+233182085+54137
________________
/ ______
1 / 137 \/ 2085 1
x3 = - + 3 / --- + -------- + -----------------------
3 \/ 54 18 ________________
/ ______
/ 137 \/ 2085
9*3 / --- + --------
\/ 54 18
x3=93182085+541371+31+3182085+54137
x3 = 1/(9*(sqrt(2085)/18 + 137/54)^(1/3)) + 1/3 + (sqrt(2085)/18 + 137/54)^(1/3)
Suma y producto de raíces
[src]
________________ / ________________ \ ________________ / ________________ \
/ ______ | / ______ | / ______ | / ______ |
/ 137 \/ 2085 | ___ / 137 \/ 2085 | / 137 \/ 2085 | ___ / 137 \/ 2085 | ________________
3 / --- + -------- | \/ 3 *3 / --- + -------- ___ | 3 / --- + -------- |\/ 3 *3 / --- + -------- ___ | / ______
1 \/ 54 18 1 | \/ 54 18 \/ 3 | 1 \/ 54 18 1 | \/ 54 18 \/ 3 | 1 / 137 \/ 2085 1
- - --------------------- - ------------------------ + I*|- --------------------------- + ------------------------| + - - --------------------- - ------------------------ + I*|--------------------------- - ------------------------| + - + 3 / --- + -------- + -----------------------
3 2 ________________ | 2 ________________| 3 2 ________________ | 2 ________________| 3 \/ 54 18 ________________
/ ______ | / ______ | / ______ | / ______ | / ______
/ 137 \/ 2085 | / 137 \/ 2085 | / 137 \/ 2085 | / 137 \/ 2085 | / 137 \/ 2085
18*3 / --- + -------- | 18*3 / --- + -------- | 18*3 / --- + -------- | 18*3 / --- + -------- | 9*3 / --- + --------
\/ 54 18 \ \/ 54 18 / \/ 54 18 \ \/ 54 18 / \/ 54 18
93182085+541371+31+3182085+54137+−23182085+54137−183182085+541371+31+i−233182085+54137+183182085+541373+−23182085+54137−183182085+541371+31+i−183182085+541373+233182085+54137
/ ________________ \ / ________________ \
| / ______ | | / ______ |
| ___ / 137 \/ 2085 | | ___ / 137 \/ 2085 |
|\/ 3 *3 / --- + -------- ___ | | \/ 3 *3 / --- + -------- ___ |
| \/ 54 18 \/ 3 | | \/ 54 18 \/ 3 |
1 + I*|--------------------------- - ------------------------| + I*|- --------------------------- + ------------------------|
| 2 ________________| | 2 ________________|
| / ______ | | / ______ |
| / 137 \/ 2085 | | / 137 \/ 2085 |
| 18*3 / --- + -------- | | 18*3 / --- + -------- |
\ \/ 54 18 / \ \/ 54 18 /
1+i−233182085+54137+183182085+541373+i−183182085+541373+233182085+54137
/ ________________ / ________________ \\ / ________________ / ________________ \\
| / ______ | / ______ || | / ______ | / ______ ||
| / 137 \/ 2085 | ___ / 137 \/ 2085 || | / 137 \/ 2085 | ___ / 137 \/ 2085 || / ________________ \
| 3 / --- + -------- | \/ 3 *3 / --- + -------- ___ || | 3 / --- + -------- |\/ 3 *3 / --- + -------- ___ || | / ______ |
|1 \/ 54 18 1 | \/ 54 18 \/ 3 || |1 \/ 54 18 1 | \/ 54 18 \/ 3 || |1 / 137 \/ 2085 1 |
|- - --------------------- - ------------------------ + I*|- --------------------------- + ------------------------||*|- - --------------------- - ------------------------ + I*|--------------------------- - ------------------------||*|- + 3 / --- + -------- + -----------------------|
|3 2 ________________ | 2 ________________|| |3 2 ________________ | 2 ________________|| |3 \/ 54 18 ________________|
| / ______ | / ______ || | / ______ | / ______ || | / ______ |
| / 137 \/ 2085 | / 137 \/ 2085 || | / 137 \/ 2085 | / 137 \/ 2085 || | / 137 \/ 2085 |
| 18*3 / --- + -------- | 18*3 / --- + -------- || | 18*3 / --- + -------- | 18*3 / --- + -------- || | 9*3 / --- + -------- |
\ \/ 54 18 \ \/ 54 18 // \ \/ 54 18 \ \/ 54 18 // \ \/ 54 18 /
−23182085+54137−183182085+541371+31+i−183182085+541373+233182085+54137−23182085+54137−183182085+541371+31+i−233182085+54137+183182085+54137393182085+541371+31+3182085+54137
x1 = -0.558171649312106 - 1.43213479425353*i
x2 = -0.558171649312106 + 1.43213479425353*i