cos^3x-cos^2x-cosx=1/3 la ecuación
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Solución
Gráfica
/ / / ___\\\ / / / ___\\\
| | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 |||
| | 2/3 2*\/ 2 *|- - - -------||| | | 2/3 2*\/ 2 *|- - - -------|||
| |1 2 \ 2 2 /|| | |1 2 \ 2 2 /||
x1 = - re|acos|- + ----------------- + -----------------------|| + 2*pi - I*im|acos|- + ----------------- + -----------------------||
| |3 / ___\ 3 || | |3 / ___\ 3 ||
| | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | ||
| | 3*|- - - -------| || | | 3*|- - - -------| ||
\ \ \ 2 2 / // \ \ \ 2 2 / //
x1=−reacos31+3232(−21−23i)+3(−21−23i)232+2π−iimacos31+3232(−21−23i)+3(−21−23i)232
/ / / ___\\\ / / / ___\\\
| | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 |||
| | 2/3 2*\/ 2 *|- - + -------||| | | 2/3 2*\/ 2 *|- - + -------|||
| |1 2 \ 2 2 /|| | |1 2 \ 2 2 /||
x2 = - re|acos|- + ----------------- + -----------------------|| + 2*pi - I*im|acos|- + ----------------- + -----------------------||
| |3 / ___\ 3 || | |3 / ___\ 3 ||
| | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | ||
| | 3*|- - + -------| || | | 3*|- - + -------| ||
\ \ \ 2 2 / // \ \ \ 2 2 / //
x2=−reacos31+3(−21+23i)232+3232(−21+23i)+2π−iimacos31+3(−21+23i)232+3232(−21+23i)
/ / / ___\\\ / / / ___\\\
| | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 |||
| | 2/3 2*\/ 2 *|- - - -------||| | | 2/3 2*\/ 2 *|- - - -------|||
| |1 2 \ 2 2 /|| | |1 2 \ 2 2 /||
x3 = I*im|acos|- + ----------------- + -----------------------|| + re|acos|- + ----------------- + -----------------------||
| |3 / ___\ 3 || | |3 / ___\ 3 ||
| | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | ||
| | 3*|- - - -------| || | | 3*|- - - -------| ||
\ \ \ 2 2 / // \ \ \ 2 2 / //
x3=reacos31+3232(−21−23i)+3(−21−23i)232+iimacos31+3232(−21−23i)+3(−21−23i)232
/ / / ___\\\ / / / ___\\\
| | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 |||
| | 2/3 2*\/ 2 *|- - + -------||| | | 2/3 2*\/ 2 *|- - + -------|||
| |1 2 \ 2 2 /|| | |1 2 \ 2 2 /||
x4 = I*im|acos|- + ----------------- + -----------------------|| + re|acos|- + ----------------- + -----------------------||
| |3 / ___\ 3 || | |3 / ___\ 3 ||
| | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | ||
| | 3*|- - + -------| || | | 3*|- - + -------| ||
\ \ \ 2 2 / // \ \ \ 2 2 / //
x4=reacos31+3(−21+23i)232+3232(−21+23i)+iimacos31+3(−21+23i)232+3232(−21+23i)
/ / 2/3 3 ___\\
| |1 2 2*\/ 2 ||
x5 = 2*pi - I*im|acos|- + ---- + -------||
\ \3 3 3 //
x5=2π−iim(acos(31+3232+3232))
/ / 2/3 3 ___\\ / / 2/3 3 ___\\
| |1 2 2*\/ 2 || | |1 2 2*\/ 2 ||
x6 = I*im|acos|- + ---- + -------|| + re|acos|- + ---- + -------||
\ \3 3 3 // \ \3 3 3 //
x6=re(acos(31+3232+3232))+iim(acos(31+3232+3232))
x6 = re(acos(1/3 + 2^(2/3)/3 + 2*2^(1/3)/3)) + i*im(acos(1/3 + 2^(2/3)/3 + 2*2^(1/3)/3))
Suma y producto de raíces
[src]
/ / / ___\\\ / / / ___\\\ / / / ___\\\ / / / ___\\\ / / / ___\\\ / / / ___\\\ / / / ___\\\ / / / ___\\\
| | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 |||
| | 2/3 2*\/ 2 *|- - - -------||| | | 2/3 2*\/ 2 *|- - - -------||| | | 2/3 2*\/ 2 *|- - + -------||| | | 2/3 2*\/ 2 *|- - + -------||| | | 2/3 2*\/ 2 *|- - - -------||| | | 2/3 2*\/ 2 *|- - - -------||| | | 2/3 2*\/ 2 *|- - + -------||| | | 2/3 2*\/ 2 *|- - + -------||| / / 2/3 3 ___\\ / / 2/3 3 ___\\ / / 2/3 3 ___\\
| |1 2 \ 2 2 /|| | |1 2 \ 2 2 /|| | |1 2 \ 2 2 /|| | |1 2 \ 2 2 /|| | |1 2 \ 2 2 /|| | |1 2 \ 2 2 /|| | |1 2 \ 2 2 /|| | |1 2 \ 2 2 /|| | |1 2 2*\/ 2 || | |1 2 2*\/ 2 || | |1 2 2*\/ 2 ||
- re|acos|- + ----------------- + -----------------------|| + 2*pi - I*im|acos|- + ----------------- + -----------------------|| + - re|acos|- + ----------------- + -----------------------|| + 2*pi - I*im|acos|- + ----------------- + -----------------------|| + I*im|acos|- + ----------------- + -----------------------|| + re|acos|- + ----------------- + -----------------------|| + I*im|acos|- + ----------------- + -----------------------|| + re|acos|- + ----------------- + -----------------------|| + 2*pi - I*im|acos|- + ---- + -------|| + I*im|acos|- + ---- + -------|| + re|acos|- + ---- + -------||
| |3 / ___\ 3 || | |3 / ___\ 3 || | |3 / ___\ 3 || | |3 / ___\ 3 || | |3 / ___\ 3 || | |3 / ___\ 3 || | |3 / ___\ 3 || | |3 / ___\ 3 || \ \3 3 3 // \ \3 3 3 // \ \3 3 3 //
| | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | ||
| | 3*|- - - -------| || | | 3*|- - - -------| || | | 3*|- - + -------| || | | 3*|- - + -------| || | | 3*|- - - -------| || | | 3*|- - - -------| || | | 3*|- - + -------| || | | 3*|- - + -------| ||
\ \ \ 2 2 / // \ \ \ 2 2 / // \ \ \ 2 2 / // \ \ \ 2 2 / // \ \ \ 2 2 / // \ \ \ 2 2 / // \ \ \ 2 2 / // \ \ \ 2 2 / //
(2π−iim(acos(31+3232+3232)))+reacos31+3(−21+23i)232+3232(−21+23i)+iimacos31+3(−21+23i)232+3232(−21+23i)+−reacos31+3232(−21−23i)+3(−21−23i)232+2π−iimacos31+3232(−21−23i)+3(−21−23i)232+−reacos31+3(−21+23i)232+3232(−21+23i)+2π−iimacos31+3(−21+23i)232+3232(−21+23i)+reacos31+3232(−21−23i)+3(−21−23i)232+iimacos31+3232(−21−23i)+3(−21−23i)232+(re(acos(31+3232+3232))+iim(acos(31+3232+3232)))
/ / 2/3 3 ___\\
| |1 2 2*\/ 2 ||
6*pi + re|acos|- + ---- + -------||
\ \3 3 3 //
re(acos(31+3232+3232))+6π
/ / / / ___\\\ / / / ___\\\\ / / / / ___\\\ / / / ___\\\\ / / / / ___\\\ / / / ___\\\\ / / / / ___\\\ / / / ___\\\\
| | | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 |||| | | | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 |||| | | | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 |||| | | | 3 ___ | 1 I*\/ 3 ||| | | 3 ___ | 1 I*\/ 3 ||||
| | | 2/3 2*\/ 2 *|- - - -------||| | | 2/3 2*\/ 2 *|- - - -------|||| | | | 2/3 2*\/ 2 *|- - + -------||| | | 2/3 2*\/ 2 *|- - + -------|||| | | | 2/3 2*\/ 2 *|- - - -------||| | | 2/3 2*\/ 2 *|- - - -------|||| | | | 2/3 2*\/ 2 *|- - + -------||| | | 2/3 2*\/ 2 *|- - + -------|||| / / / 2/3 3 ___\\\ / / / 2/3 3 ___\\ / / 2/3 3 ___\\\
| | |1 2 \ 2 2 /|| | |1 2 \ 2 2 /||| | | |1 2 \ 2 2 /|| | |1 2 \ 2 2 /||| | | |1 2 \ 2 2 /|| | |1 2 \ 2 2 /||| | | |1 2 \ 2 2 /|| | |1 2 \ 2 2 /||| | | |1 2 2*\/ 2 ||| | | |1 2 2*\/ 2 || | |1 2 2*\/ 2 |||
|- re|acos|- + ----------------- + -----------------------|| + 2*pi - I*im|acos|- + ----------------- + -----------------------|||*|- re|acos|- + ----------------- + -----------------------|| + 2*pi - I*im|acos|- + ----------------- + -----------------------|||*|I*im|acos|- + ----------------- + -----------------------|| + re|acos|- + ----------------- + -----------------------|||*|I*im|acos|- + ----------------- + -----------------------|| + re|acos|- + ----------------- + -----------------------|||*|2*pi - I*im|acos|- + ---- + -------|||*|I*im|acos|- + ---- + -------|| + re|acos|- + ---- + -------|||
| | |3 / ___\ 3 || | |3 / ___\ 3 ||| | | |3 / ___\ 3 || | |3 / ___\ 3 ||| | | |3 / ___\ 3 || | |3 / ___\ 3 ||| | | |3 / ___\ 3 || | |3 / ___\ 3 ||| \ \ \3 3 3 /// \ \ \3 3 3 // \ \3 3 3 ///
| | | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | ||| | | | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | ||| | | | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | ||| | | | | 1 I*\/ 3 | || | | | 1 I*\/ 3 | |||
| | | 3*|- - - -------| || | | 3*|- - - -------| ||| | | | 3*|- - + -------| || | | 3*|- - + -------| ||| | | | 3*|- - - -------| || | | 3*|- - - -------| ||| | | | 3*|- - + -------| || | | 3*|- - + -------| |||
\ \ \ \ 2 2 / // \ \ \ 2 2 / /// \ \ \ \ 2 2 / // \ \ \ 2 2 / /// \ \ \ \ 2 2 / // \ \ \ 2 2 / /// \ \ \ \ 2 2 / // \ \ \ 2 2 / ///
−reacos31+3232(−21−23i)+3(−21−23i)232+2π−iimacos31+3232(−21−23i)+3(−21−23i)232−reacos31+3(−21+23i)232+3232(−21+23i)+2π−iimacos31+3(−21+23i)232+3232(−21+23i)reacos31+3232(−21−23i)+3(−21−23i)232+iimacos31+3232(−21−23i)+3(−21−23i)232reacos31+3(−21+23i)232+3232(−21+23i)+iimacos31+3(−21+23i)232+3232(−21+23i)(2π−iim(acos(31+3232+3232)))(re(acos(31+3232+3232))+iim(acos(31+3232+3232)))
/ / / 2/3 3 ___\\\ / / / 2/3 3 ___\\ / / 2/3 3 ___\\\ / / / 3 ___ 2/3 3 ___ ___ 2/3 ___\\ / / 3 ___ 2/3 3 ___ ___ 2/3 ___\\\ / / / 3 ___ 2/3 2/3 ___ 3 ___ ___\\ / / 3 ___ 2/3 2/3 ___ 3 ___ ___\\\ / / / 3 ___ 2/3 3 ___ ___ 2/3 ___\\ / / 3 ___ 2/3 3 ___ ___ 2/3 ___\\\ / / / 3 ___ 2/3 2/3 ___ 3 ___ ___\\ / / 3 ___ 2/3 2/3 ___ 3 ___ ___\\\
| | |1 2 2*\/ 2 ||| | | |1 2 2*\/ 2 || | |1 2 2*\/ 2 ||| | | |1 \/ 2 2 I*\/ 2 *\/ 3 I*2 *\/ 3 || | |1 \/ 2 2 I*\/ 2 *\/ 3 I*2 *\/ 3 ||| | | |1 \/ 2 2 I*2 *\/ 3 I*\/ 2 *\/ 3 || | |1 \/ 2 2 I*2 *\/ 3 I*\/ 2 *\/ 3 ||| | | |1 \/ 2 2 I*\/ 2 *\/ 3 I*2 *\/ 3 || | |1 \/ 2 2 I*\/ 2 *\/ 3 I*2 *\/ 3 ||| | | |1 \/ 2 2 I*2 *\/ 3 I*\/ 2 *\/ 3 || | |1 \/ 2 2 I*2 *\/ 3 I*\/ 2 *\/ 3 |||
|2*pi - I*im|acos|- + ---- + -------|||*|I*im|acos|- + ---- + -------|| + re|acos|- + ---- + -------|||*|I*im|acos|- - ----- - ---- - ------------- + ------------|| + re|acos|- - ----- - ---- - ------------- + ------------|||*|I*im|acos|- - ----- - ---- - ------------ + -------------|| + re|acos|- - ----- - ---- - ------------ + -------------|||*|-2*pi + I*im|acos|- - ----- - ---- - ------------- + ------------|| + re|acos|- - ----- - ---- - ------------- + ------------|||*|-2*pi + I*im|acos|- - ----- - ---- - ------------ + -------------|| + re|acos|- - ----- - ---- - ------------ + -------------|||
\ \ \3 3 3 /// \ \ \3 3 3 // \ \3 3 3 /// \ \ \3 3 6 3 6 // \ \3 3 6 3 6 /// \ \ \3 3 6 6 3 // \ \3 3 6 6 3 /// \ \ \3 3 6 3 6 // \ \3 3 6 3 6 /// \ \ \3 3 6 6 3 // \ \3 3 6 6 3 ///
(2π−iim(acos(31+3232+3232)))(re(acos(31+3232+3232))+iim(acos(31+3232+3232)))(re(acos(−332−6232+31−3323i+62323i))+iim(acos(−332−6232+31−3323i+62323i)))(re(acos(−332−6232+31−62323i+3323i))+iim(acos(−332−6232+31−62323i+3323i)))(−2π+re(acos(−332−6232+31−3323i+62323i))+iim(acos(−332−6232+31−3323i+62323i)))(−2π+re(acos(−332−6232+31−62323i+3323i))+iim(acos(−332−6232+31−62323i+3323i)))
(2*pi - i*im(acos(1/3 + 2^(2/3)/3 + 2*2^(1/3)/3)))*(i*im(acos(1/3 + 2^(2/3)/3 + 2*2^(1/3)/3)) + re(acos(1/3 + 2^(2/3)/3 + 2*2^(1/3)/3)))*(i*im(acos(1/3 - 2^(1/3)/3 - 2^(2/3)/6 - i*2^(1/3)*sqrt(3)/3 + i*2^(2/3)*sqrt(3)/6)) + re(acos(1/3 - 2^(1/3)/3 - 2^(2/3)/6 - i*2^(1/3)*sqrt(3)/3 + i*2^(2/3)*sqrt(3)/6)))*(i*im(acos(1/3 - 2^(1/3)/3 - 2^(2/3)/6 - i*2^(2/3)*sqrt(3)/6 + i*2^(1/3)*sqrt(3)/3)) + re(acos(1/3 - 2^(1/3)/3 - 2^(2/3)/6 - i*2^(2/3)*sqrt(3)/6 + i*2^(1/3)*sqrt(3)/3)))*(-2*pi + i*im(acos(1/3 - 2^(1/3)/3 - 2^(2/3)/6 - i*2^(1/3)*sqrt(3)/3 + i*2^(2/3)*sqrt(3)/6)) + re(acos(1/3 - 2^(1/3)/3 - 2^(2/3)/6 - i*2^(1/3)*sqrt(3)/3 + i*2^(2/3)*sqrt(3)/6)))*(-2*pi + i*im(acos(1/3 - 2^(1/3)/3 - 2^(2/3)/6 - i*2^(2/3)*sqrt(3)/6 + i*2^(1/3)*sqrt(3)/3)) + re(acos(1/3 - 2^(1/3)/3 - 2^(2/3)/6 - i*2^(2/3)*sqrt(3)/6 + i*2^(1/3)*sqrt(3)/3)))
x1 = 6.28318530717959 - 1.12498528475449*i
x2 = 4.36794711519116 - 0.282208350633355*i
x3 = 4.36794711519116 + 0.282208350633355*i
x5 = 1.91523819198842 + 0.282208350633355*i
x6 = 1.91523819198842 - 0.282208350633355*i
x6 = 1.91523819198842 - 0.282208350633355*i