Sr Examen

Otras calculadoras

(10a+b)(a+b)=405 la ecuación

El profesor se sorprenderá mucho al ver tu solución correcta😉

v

Solución numérica:

Buscar la solución numérica en el intervalo [, ]

Solución

Ha introducido [src]
(10*a + b)*(a + b) = 405
$$\left(a + b\right) \left(10 a + b\right) = 405$$
Solución detallada
Transportemos el miembro derecho de la ecuación al
miembro izquierdo de la ecuación con el signo negativo.

La ecuación se convierte de
$$\left(a + b\right) \left(10 a + b\right) = 405$$
en
$$\left(a + b\right) \left(10 a + b\right) - 405 = 0$$
Abramos la expresión en la ecuación
$$\left(a + b\right) \left(10 a + b\right) - 405 = 0$$
Obtenemos la ecuación cuadrática
$$10 a^{2} + 11 a b + b^{2} - 405 = 0$$
Es la ecuación de la forma
a*b^2 + b*b + c = 0

La ecuación cuadrática puede ser resuelta
con la ayuda del discriminante.
Las raíces de la ecuación cuadrática:
$$b_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$b_{2} = \frac{- \sqrt{D} - b}{2 a}$$
donde D = b^2 - 4*a*c es el discriminante.
Como
$$a = 1$$
$$b = 11 a$$
$$c = 10 a^{2} - 405$$
, entonces
D = b^2 - 4 * a * c = 

(11*a)^2 - 4 * (1) * (-405 + 10*a^2) = 1620 + 81*a^2

La ecuación tiene dos raíces.
b1 = (-b + sqrt(D)) / (2*a)

b2 = (-b - sqrt(D)) / (2*a)

o
$$b_{1} = - \frac{11 a}{2} + \frac{\sqrt{81 a^{2} + 1620}}{2}$$
$$b_{2} = - \frac{11 a}{2} - \frac{\sqrt{81 a^{2} + 1620}}{2}$$
Gráfica
Suma y producto de raíces [src]
suma
               /                   ___________________________________________                                                \         ___________________________________________                                                                  /                   ___________________________________________                                                \         ___________________________________________                                                
               |                  /                       2                       /     /                      2        2   \\|        /                       2                       /     /                      2        2   \\                  |                  /                       2                       /     /                      2        2   \\|        /                       2                       /     /                      2        2   \\
               |               4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/||     4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/|                  |               4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/||     4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/|
               |             9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *sin|------------------------------------------||   9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *cos|------------------------------------------|                  |             9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *sin|------------------------------------------||   9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *cos|------------------------------------------|
  11*re(a)     |  11*im(a)                                                        \                    2                     /|                                                        \                    2                     /     11*re(a)     |  11*im(a)                                                        \                    2                     /|                                                        \                    2                     /
- -------- + I*|- -------- - -------------------------------------------------------------------------------------------------| - ------------------------------------------------------------------------------------------------- + - -------- + I*|- -------- + -------------------------------------------------------------------------------------------------| + -------------------------------------------------------------------------------------------------
     2         \     2                                                       2                                                /                                                   2                                                        2         \     2                                                       2                                                /                                                   2                                                
$$\left(i \left(- \frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{im}{\left(a\right)}}{2}\right) - \frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{re}{\left(a\right)}}{2}\right) + \left(i \left(\frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{im}{\left(a\right)}}{2}\right) + \frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{re}{\left(a\right)}}{2}\right)$$
=
              /                   ___________________________________________                                                \     /                   ___________________________________________                                                \
              |                  /                       2                       /     /                      2        2   \\|     |                  /                       2                       /     /                      2        2   \\|
              |               4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/||     |               4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/||
              |             9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *sin|------------------------------------------||     |             9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *sin|------------------------------------------||
              |  11*im(a)                                                        \                    2                     /|     |  11*im(a)                                                        \                    2                     /|
-11*re(a) + I*|- -------- - -------------------------------------------------------------------------------------------------| + I*|- -------- + -------------------------------------------------------------------------------------------------|
              \     2                                                       2                                                /     \     2                                                       2                                                /
$$i \left(- \frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{im}{\left(a\right)}}{2}\right) + i \left(\frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{im}{\left(a\right)}}{2}\right) - 11 \operatorname{re}{\left(a\right)}$$
producto
/               /                   ___________________________________________                                                \         ___________________________________________                                                \ /               /                   ___________________________________________                                                \         ___________________________________________                                                \
|               |                  /                       2                       /     /                      2        2   \\|        /                       2                       /     /                      2        2   \\| |               |                  /                       2                       /     /                      2        2   \\|        /                       2                       /     /                      2        2   \\|
|               |               4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/||     4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/|| |               |               4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/||     4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/||
|               |             9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *sin|------------------------------------------||   9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *cos|------------------------------------------|| |               |             9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *sin|------------------------------------------||   9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *cos|------------------------------------------||
|  11*re(a)     |  11*im(a)                                                        \                    2                     /|                                                        \                    2                     /| |  11*re(a)     |  11*im(a)                                                        \                    2                     /|                                                        \                    2                     /|
|- -------- + I*|- -------- - -------------------------------------------------------------------------------------------------| - -------------------------------------------------------------------------------------------------|*|- -------- + I*|- -------- + -------------------------------------------------------------------------------------------------| + -------------------------------------------------------------------------------------------------|
\     2         \     2                                                       2                                                /                                                   2                                                / \     2         \     2                                                       2                                                /                                                   2                                                /
$$\left(i \left(- \frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{im}{\left(a\right)}}{2}\right) - \frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{re}{\left(a\right)}}{2}\right) \left(i \left(\frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{im}{\left(a\right)}}{2}\right) + \frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{re}{\left(a\right)}}{2}\right)$$
=
            2           2                      
-405 - 10*im (a) + 10*re (a) + 20*I*im(a)*re(a)
$$10 \left(\operatorname{re}{\left(a\right)}\right)^{2} + 20 i \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)} - 10 \left(\operatorname{im}{\left(a\right)}\right)^{2} - 405$$
-405 - 10*im(a)^2 + 10*re(a)^2 + 20*i*im(a)*re(a)
Respuesta rápida [src]
                    /                   ___________________________________________                                                \         ___________________________________________                                                
                    |                  /                       2                       /     /                      2        2   \\|        /                       2                       /     /                      2        2   \\
                    |               4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/||     4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/|
                    |             9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *sin|------------------------------------------||   9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *cos|------------------------------------------|
       11*re(a)     |  11*im(a)                                                        \                    2                     /|                                                        \                    2                     /
b1 = - -------- + I*|- -------- - -------------------------------------------------------------------------------------------------| - -------------------------------------------------------------------------------------------------
          2         \     2                                                       2                                                /                                                   2                                                
$$b_{1} = i \left(- \frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{im}{\left(a\right)}}{2}\right) - \frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{re}{\left(a\right)}}{2}$$
                    /                   ___________________________________________                                                \         ___________________________________________                                                
                    |                  /                       2                       /     /                      2        2   \\|        /                       2                       /     /                      2        2   \\
                    |               4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/||     4 /  /       2        2   \        2      2        |atan2\2*im(a)*re(a), 20 + re (a) - im (a)/|
                    |             9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *sin|------------------------------------------||   9*\/   \20 + re (a) - im (a)/  + 4*im (a)*re (a) *cos|------------------------------------------|
       11*re(a)     |  11*im(a)                                                        \                    2                     /|                                                        \                    2                     /
b2 = - -------- + I*|- -------- + -------------------------------------------------------------------------------------------------| + -------------------------------------------------------------------------------------------------
          2         \     2                                                       2                                                /                                                   2                                                
$$b_{2} = i \left(\frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \sin{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{im}{\left(a\right)}}{2}\right) + \frac{9 \sqrt[4]{\left(\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20\right)^{2} + 4 \left(\operatorname{re}{\left(a\right)}\right)^{2} \left(\operatorname{im}{\left(a\right)}\right)^{2}} \cos{\left(\frac{\operatorname{atan_{2}}{\left(2 \operatorname{re}{\left(a\right)} \operatorname{im}{\left(a\right)},\left(\operatorname{re}{\left(a\right)}\right)^{2} - \left(\operatorname{im}{\left(a\right)}\right)^{2} + 20 \right)}}{2} \right)}}{2} - \frac{11 \operatorname{re}{\left(a\right)}}{2}$$
b2 = i*(9*((re(a)^2 - im(a)^2 + 20)^2 + 4*re(a)^2*im(a)^2)^(1/4)*sin(atan2(2*re(a)*im(a, re(a)^2 - im(a)^2 + 20)/2)/2 - 11*im(a)/2) + 9*((re(a)^2 - im(a)^2 + 20)^2 + 4*re(a)^2*im(a)^2)^(1/4)*cos(atan2(2*re(a)*im(a), re(a)^2 - im(a)^2 + 20)/2)/2 - 11*re(a)/2)