Sr Examen

Derivada de (xsecx)^2

Función f() - derivada -er orden en el punto
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Gráfico:

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Solución

Ha introducido [src]
          2
(x*sec(x)) 
(xsec(x))2\left(x \sec{\left(x \right)}\right)^{2}
(x*sec(x))^2
Solución detallada
  1. Sustituimos u=xsec(x)u = x \sec{\left(x \right)}.

  2. Según el principio, aplicamos: u2u^{2} tenemos 2u2 u

  3. Luego se aplica una cadena de reglas. Multiplicamos por ddxxsec(x)\frac{d}{d x} x \sec{\left(x \right)}:

    1. Se aplica la regla de la derivada de una multiplicación:

      ddxf(x)g(x)=f(x)ddxg(x)+g(x)ddxf(x)\frac{d}{d x} f{\left(x \right)} g{\left(x \right)} = f{\left(x \right)} \frac{d}{d x} g{\left(x \right)} + g{\left(x \right)} \frac{d}{d x} f{\left(x \right)}

      f(x)=xf{\left(x \right)} = x; calculamos ddxf(x)\frac{d}{d x} f{\left(x \right)}:

      1. Según el principio, aplicamos: xx tenemos 11

      g(x)=sec(x)g{\left(x \right)} = \sec{\left(x \right)}; calculamos ddxg(x)\frac{d}{d x} g{\left(x \right)}:

      1. Reescribimos las funciones para diferenciar:

        sec(x)=1cos(x)\sec{\left(x \right)} = \frac{1}{\cos{\left(x \right)}}

      2. Sustituimos u=cos(x)u = \cos{\left(x \right)}.

      3. Según el principio, aplicamos: 1u\frac{1}{u} tenemos 1u2- \frac{1}{u^{2}}

      4. Luego se aplica una cadena de reglas. Multiplicamos por ddxcos(x)\frac{d}{d x} \cos{\left(x \right)}:

        1. La derivada del coseno es igual a menos el seno:

          ddxcos(x)=sin(x)\frac{d}{d x} \cos{\left(x \right)} = - \sin{\left(x \right)}

        Como resultado de la secuencia de reglas:

        sin(x)cos2(x)\frac{\sin{\left(x \right)}}{\cos^{2}{\left(x \right)}}

      Como resultado de: xsin(x)cos2(x)+sec(x)\frac{x \sin{\left(x \right)}}{\cos^{2}{\left(x \right)}} + \sec{\left(x \right)}

    Como resultado de la secuencia de reglas:

    2x(xsin(x)cos2(x)+sec(x))sec(x)2 x \left(\frac{x \sin{\left(x \right)}}{\cos^{2}{\left(x \right)}} + \sec{\left(x \right)}\right) \sec{\left(x \right)}

  4. Simplificamos:

    2x(xtan(x)+1)cos2(x)\frac{2 x \left(x \tan{\left(x \right)} + 1\right)}{\cos^{2}{\left(x \right)}}


Respuesta:

2x(xtan(x)+1)cos2(x)\frac{2 x \left(x \tan{\left(x \right)} + 1\right)}{\cos^{2}{\left(x \right)}}

Gráfica
02468-8-6-4-2-1010-25000002500000
Primera derivada [src]
 2    2                                  
x *sec (x)*(2*sec(x) + 2*x*sec(x)*tan(x))
-----------------------------------------
                 x*sec(x)                
x2sec2(x)(2xtan(x)sec(x)+2sec(x))xsec(x)\frac{x^{2} \sec^{2}{\left(x \right)} \left(2 x \tan{\left(x \right)} \sec{\left(x \right)} + 2 \sec{\left(x \right)}\right)}{x \sec{\left(x \right)}}
Segunda derivada [src]
     2    /                     2     /                2        /       2   \\                                     \
2*sec (x)*\-1 + 2*(1 + x*tan(x))  + x*\2*tan(x) + x*tan (x) + x*\1 + tan (x)// - x*tan(x) - x*(1 + x*tan(x))*tan(x)/
2(x(xtan(x)+1)tan(x)+x(x(tan2(x)+1)+xtan2(x)+2tan(x))xtan(x)+2(xtan(x)+1)21)sec2(x)2 \left(- x \left(x \tan{\left(x \right)} + 1\right) \tan{\left(x \right)} + x \left(x \left(\tan^{2}{\left(x \right)} + 1\right) + x \tan^{2}{\left(x \right)} + 2 \tan{\left(x \right)}\right) - x \tan{\left(x \right)} + 2 \left(x \tan{\left(x \right)} + 1\right)^{2} - 1\right) \sec^{2}{\left(x \right)}
Tercera derivada [src]
          /                                                                           2                                                                                                                                                                                                 /     2 /       2   \      2    2                \\
     2    |  /         2           3          /       2   \       \   2*(1 + x*tan(x))                    2                                                     /                2        /       2   \\        2                       /       2   \                  2*(1 + x*tan(x))*\1 + x *\1 + tan (x)/ + 2*x *tan (x) + 4*x*tan(x)/|
2*sec (x)*|x*\3 + 6*tan (x) + x*tan (x) + 5*x*\1 + tan (x)/*tan(x)/ - ----------------- - 2*(1 + x*tan(x)) *tan(x) - 2*(1 + x*tan(x))*tan(x) + 2*(1 + x*tan(x))*\2*tan(x) + x*tan (x) + x*\1 + tan (x)// - x*tan (x)*(1 + x*tan(x)) - x*\1 + tan (x)/*(1 + x*tan(x)) + -------------------------------------------------------------------|
          \                                                                   x                                                                                                                                                                                                                         x                                 /
2(x(xtan(x)+1)(tan2(x)+1)x(xtan(x)+1)tan2(x)+x(5x(tan2(x)+1)tan(x)+xtan3(x)+6tan2(x)+3)2(xtan(x)+1)2tan(x)+2(xtan(x)+1)(x(tan2(x)+1)+xtan2(x)+2tan(x))2(xtan(x)+1)tan(x)2(xtan(x)+1)2x+2(xtan(x)+1)(x2(tan2(x)+1)+2x2tan2(x)+4xtan(x)+1)x)sec2(x)2 \left(- x \left(x \tan{\left(x \right)} + 1\right) \left(\tan^{2}{\left(x \right)} + 1\right) - x \left(x \tan{\left(x \right)} + 1\right) \tan^{2}{\left(x \right)} + x \left(5 x \left(\tan^{2}{\left(x \right)} + 1\right) \tan{\left(x \right)} + x \tan^{3}{\left(x \right)} + 6 \tan^{2}{\left(x \right)} + 3\right) - 2 \left(x \tan{\left(x \right)} + 1\right)^{2} \tan{\left(x \right)} + 2 \left(x \tan{\left(x \right)} + 1\right) \left(x \left(\tan^{2}{\left(x \right)} + 1\right) + x \tan^{2}{\left(x \right)} + 2 \tan{\left(x \right)}\right) - 2 \left(x \tan{\left(x \right)} + 1\right) \tan{\left(x \right)} - \frac{2 \left(x \tan{\left(x \right)} + 1\right)^{2}}{x} + \frac{2 \left(x \tan{\left(x \right)} + 1\right) \left(x^{2} \left(\tan^{2}{\left(x \right)} + 1\right) + 2 x^{2} \tan^{2}{\left(x \right)} + 4 x \tan{\left(x \right)} + 1\right)}{x}\right) \sec^{2}{\left(x \right)}
Gráfico
Derivada de (xsecx)^2