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-3sinx-1+cos^2(x)=0 la ecuación

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Solución numérica:

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Solución

Ha introducido [src]
                   2       
-3*sin(x) - 1 + cos (x) = 0
(3sin(x)1)+cos2(x)=0\left(- 3 \sin{\left(x \right)} - 1\right) + \cos^{2}{\left(x \right)} = 0
Solución detallada
Tenemos la ecuación
(3sin(x)1)+cos2(x)=0\left(- 3 \sin{\left(x \right)} - 1\right) + \cos^{2}{\left(x \right)} = 0
cambiamos
(sin(x)+3)sin(x)=0- \left(\sin{\left(x \right)} + 3\right) \sin{\left(x \right)} = 0
sin2(x)3sin(x)=0- \sin^{2}{\left(x \right)} - 3 \sin{\left(x \right)} = 0
Sustituimos
w=sin(x)w = \sin{\left(x \right)}
Es la ecuación de la forma
a*w^2 + b*w + c = 0

La ecuación cuadrática puede ser resuelta
con la ayuda del discriminante.
Las raíces de la ecuación cuadrática:
w1=Db2aw_{1} = \frac{\sqrt{D} - b}{2 a}
w2=Db2aw_{2} = \frac{- \sqrt{D} - b}{2 a}
donde D = b^2 - 4*a*c es el discriminante.
Como
a=1a = -1
b=3b = -3
c=0c = 0
, entonces
D = b^2 - 4 * a * c = 

(-3)^2 - 4 * (-1) * (0) = 9

Como D > 0 la ecuación tiene dos raíces.
w1 = (-b + sqrt(D)) / (2*a)

w2 = (-b - sqrt(D)) / (2*a)

o
w1=3w_{1} = -3
w2=0w_{2} = 0
hacemos cambio inverso
sin(x)=w\sin{\left(x \right)} = w
Tenemos la ecuación
sin(x)=w\sin{\left(x \right)} = w
es la ecuación trigonométrica más simple
Esta ecuación se reorganiza en
x=2πn+asin(w)x = 2 \pi n + \operatorname{asin}{\left(w \right)}
x=2πnasin(w)+πx = 2 \pi n - \operatorname{asin}{\left(w \right)} + \pi
O
x=2πn+asin(w)x = 2 \pi n + \operatorname{asin}{\left(w \right)}
x=2πnasin(w)+πx = 2 \pi n - \operatorname{asin}{\left(w \right)} + \pi
, donde n es cualquier número entero
sustituimos w:
x1=2πn+asin(w1)x_{1} = 2 \pi n + \operatorname{asin}{\left(w_{1} \right)}
x1=2πn+asin(3)x_{1} = 2 \pi n + \operatorname{asin}{\left(-3 \right)}
x1=2πnasin(3)x_{1} = 2 \pi n - \operatorname{asin}{\left(3 \right)}
x2=2πn+asin(w2)x_{2} = 2 \pi n + \operatorname{asin}{\left(w_{2} \right)}
x2=2πn+asin(0)x_{2} = 2 \pi n + \operatorname{asin}{\left(0 \right)}
x2=2πnx_{2} = 2 \pi n
x3=2πnasin(w1)+πx_{3} = 2 \pi n - \operatorname{asin}{\left(w_{1} \right)} + \pi
x3=2πn+πasin(3)x_{3} = 2 \pi n + \pi - \operatorname{asin}{\left(-3 \right)}
x3=2πn+π+asin(3)x_{3} = 2 \pi n + \pi + \operatorname{asin}{\left(3 \right)}
x4=2πnasin(w2)+πx_{4} = 2 \pi n - \operatorname{asin}{\left(w_{2} \right)} + \pi
x4=2πnasin(0)+πx_{4} = 2 \pi n - \operatorname{asin}{\left(0 \right)} + \pi
x4=2πn+πx_{4} = 2 \pi n + \pi
Gráfica
0-80-60-40-2020406080-1001005-5
Respuesta rápida [src]
x1 = 0
x1=0x_{1} = 0
           /    /          ___\\         /    /          ___\\
           |    |1   2*I*\/ 2 ||         |    |1   2*I*\/ 2 ||
x2 = - 2*re|atan|- - ---------|| - 2*I*im|atan|- - ---------||
           \    \3       3    //         \    \3       3    //
x2=2re(atan(1322i3))2iim(atan(1322i3))x_{2} = - 2 \operatorname{re}{\left(\operatorname{atan}{\left(\frac{1}{3} - \frac{2 \sqrt{2} i}{3} \right)}\right)} - 2 i \operatorname{im}{\left(\operatorname{atan}{\left(\frac{1}{3} - \frac{2 \sqrt{2} i}{3} \right)}\right)}
           /    /          ___\\         /    /          ___\\
           |    |1   2*I*\/ 2 ||         |    |1   2*I*\/ 2 ||
x3 = - 2*re|atan|- + ---------|| - 2*I*im|atan|- + ---------||
           \    \3       3    //         \    \3       3    //
x3=2re(atan(13+22i3))2iim(atan(13+22i3))x_{3} = - 2 \operatorname{re}{\left(\operatorname{atan}{\left(\frac{1}{3} + \frac{2 \sqrt{2} i}{3} \right)}\right)} - 2 i \operatorname{im}{\left(\operatorname{atan}{\left(\frac{1}{3} + \frac{2 \sqrt{2} i}{3} \right)}\right)}
x3 = -2*re(atan(1/3 + 2*sqrt(2)*i/3)) - 2*i*im(atan(1/3 + 2*sqrt(2)*i/3))
Suma y producto de raíces [src]
suma
      /    /          ___\\         /    /          ___\\         /    /          ___\\         /    /          ___\\
      |    |1   2*I*\/ 2 ||         |    |1   2*I*\/ 2 ||         |    |1   2*I*\/ 2 ||         |    |1   2*I*\/ 2 ||
- 2*re|atan|- - ---------|| - 2*I*im|atan|- - ---------|| + - 2*re|atan|- + ---------|| - 2*I*im|atan|- + ---------||
      \    \3       3    //         \    \3       3    //         \    \3       3    //         \    \3       3    //
(2re(atan(13+22i3))2iim(atan(13+22i3)))+(2re(atan(1322i3))2iim(atan(1322i3)))\left(- 2 \operatorname{re}{\left(\operatorname{atan}{\left(\frac{1}{3} + \frac{2 \sqrt{2} i}{3} \right)}\right)} - 2 i \operatorname{im}{\left(\operatorname{atan}{\left(\frac{1}{3} + \frac{2 \sqrt{2} i}{3} \right)}\right)}\right) + \left(- 2 \operatorname{re}{\left(\operatorname{atan}{\left(\frac{1}{3} - \frac{2 \sqrt{2} i}{3} \right)}\right)} - 2 i \operatorname{im}{\left(\operatorname{atan}{\left(\frac{1}{3} - \frac{2 \sqrt{2} i}{3} \right)}\right)}\right)
=
      /    /          ___\\       /    /          ___\\         /    /          ___\\         /    /          ___\\
      |    |1   2*I*\/ 2 ||       |    |1   2*I*\/ 2 ||         |    |1   2*I*\/ 2 ||         |    |1   2*I*\/ 2 ||
- 2*re|atan|- - ---------|| - 2*re|atan|- + ---------|| - 2*I*im|atan|- - ---------|| - 2*I*im|atan|- + ---------||
      \    \3       3    //       \    \3       3    //         \    \3       3    //         \    \3       3    //
2re(atan(1322i3))2re(atan(13+22i3))2iim(atan(13+22i3))2iim(atan(1322i3))- 2 \operatorname{re}{\left(\operatorname{atan}{\left(\frac{1}{3} - \frac{2 \sqrt{2} i}{3} \right)}\right)} - 2 \operatorname{re}{\left(\operatorname{atan}{\left(\frac{1}{3} + \frac{2 \sqrt{2} i}{3} \right)}\right)} - 2 i \operatorname{im}{\left(\operatorname{atan}{\left(\frac{1}{3} + \frac{2 \sqrt{2} i}{3} \right)}\right)} - 2 i \operatorname{im}{\left(\operatorname{atan}{\left(\frac{1}{3} - \frac{2 \sqrt{2} i}{3} \right)}\right)}
producto
  /      /    /          ___\\         /    /          ___\\\ /      /    /          ___\\         /    /          ___\\\
  |      |    |1   2*I*\/ 2 ||         |    |1   2*I*\/ 2 ||| |      |    |1   2*I*\/ 2 ||         |    |1   2*I*\/ 2 |||
0*|- 2*re|atan|- - ---------|| - 2*I*im|atan|- - ---------|||*|- 2*re|atan|- + ---------|| - 2*I*im|atan|- + ---------|||
  \      \    \3       3    //         \    \3       3    /// \      \    \3       3    //         \    \3       3    ///
0(2re(atan(1322i3))2iim(atan(1322i3)))(2re(atan(13+22i3))2iim(atan(13+22i3)))0 \left(- 2 \operatorname{re}{\left(\operatorname{atan}{\left(\frac{1}{3} - \frac{2 \sqrt{2} i}{3} \right)}\right)} - 2 i \operatorname{im}{\left(\operatorname{atan}{\left(\frac{1}{3} - \frac{2 \sqrt{2} i}{3} \right)}\right)}\right) \left(- 2 \operatorname{re}{\left(\operatorname{atan}{\left(\frac{1}{3} + \frac{2 \sqrt{2} i}{3} \right)}\right)} - 2 i \operatorname{im}{\left(\operatorname{atan}{\left(\frac{1}{3} + \frac{2 \sqrt{2} i}{3} \right)}\right)}\right)
=
0
00
0
Respuesta numérica [src]
x1 = 40.8407044966673
x2 = 0.0
x3 = -18.8495559215388
x4 = -56.5486677646163
x5 = 97.3893722612836
x6 = 34.5575191894877
x7 = 53.4070751110265
x8 = 47.1238898038469
x9 = -97.3893722612836
x10 = 62.8318530717959
x11 = 87.9645943005142
x12 = 43.9822971502571
x13 = 37.6991118430775
x14 = -21.9911485751286
x15 = 3.14159265358979
x16 = 65.9734457253857
x17 = 69.1150383789755
x18 = -50.2654824574367
x19 = -94.2477796076938
x20 = -75.398223686155
x21 = -53.4070751110265
x22 = 12.5663706143592
x23 = -9.42477796076938
x24 = -34.5575191894877
x25 = 21.9911485751286
x26 = -47.1238898038469
x27 = -43.9822971502571
x28 = 28.2743338823081
x29 = -31.4159265358979
x30 = -3.14159265358979
x31 = -6.28318530717959
x32 = 216.769893097696
x33 = -25.1327412287183
x34 = 31.4159265358979
x35 = -62.8318530717959
x36 = -65.9734457253857
x37 = 72.2566310325652
x38 = -59.6902604182061
x39 = -12.5663706143592
x40 = 94.2477796076938
x41 = 81.6814089933346
x42 = -91.106186954104
x43 = -100.530964914873
x44 = 59.6902604182061
x45 = -40.8407044966673
x46 = 91.106186954104
x47 = 78.5398163397448
x48 = -106.814150222053
x49 = 56.5486677646163
x50 = 84.8230016469244
x51 = 100.530964914873
x52 = -69.1150383789755
x53 = 9.42477796076938
x54 = -84.8230016469244
x55 = -78.5398163397448
x56 = -87.9645943005142
x57 = -81.6814089933346
x58 = 15.707963267949
x59 = -28.2743338823081
x60 = -15.707963267949
x61 = -37.6991118430775
x62 = 18.8495559215388
x63 = 25.1327412287183
x64 = 50.2654824574367
x65 = -72.2566310325652
x66 = 75.398223686155
x67 = 6.28318530717959
x67 = 6.28318530717959