Sr Examen
Descomponer y^4+5*y^2+7 al cuadrado
Solución
Expresión del cuadrado perfecto
Expresemos el cuadrado perfecto del trinomio cuadrático
$$\left(y^{4} + 5 y^{2}\right) + 7$$
Para eso usemos la fórmula
$$a y^{4} + b y^{2} + c = a \left(m + y^{2}\right)^{2} + n$$
donde
$$m = \frac{b}{2 a}$$
$$n = \frac{4 a c - b^{2}}{4 a}$$
En nuestro caso
$$a = 1$$
$$b = 5$$
$$c = 7$$
Entonces
$$m = \frac{5}{2}$$
$$n = \frac{3}{4}$$
Pues,
$$\left(y^{2} + \frac{5}{2}\right)^{2} + \frac{3}{4}$$
$$\left(y^{4} + 5 y^{2}\right) + 7$$
Para eso usemos la fórmula
$$a y^{4} + b y^{2} + c = a \left(m + y^{2}\right)^{2} + n$$
donde
$$m = \frac{b}{2 a}$$
$$n = \frac{4 a c - b^{2}}{4 a}$$
En nuestro caso
$$a = 1$$
$$b = 5$$
$$c = 7$$
Entonces
$$m = \frac{5}{2}$$
$$n = \frac{3}{4}$$
Pues,
$$\left(y^{2} + \frac{5}{2}\right)^{2} + \frac{3}{4}$$
Factorización
[src]
/ / / ___\\ / / ___\\\ / / / ___\\ / / ___\\\ / / / ___\\ / / ___\\\ / / / ___\\ / / ___\\\ | | |\/ 3 || | |\/ 3 ||| | | |\/ 3 || | |\/ 3 ||| | | |\/ 3 || | |\/ 3 ||| | | |\/ 3 || | |\/ 3 ||| | |atan|-----|| |atan|-----||| | |atan|-----|| |atan|-----||| | |atan|-----|| |atan|-----||| | |atan|-----|| |atan|-----||| | 4 ___ | \ 5 /| 4 ___ | \ 5 /|| | 4 ___ | \ 5 /| 4 ___ | \ 5 /|| | 4 ___ | \ 5 /| 4 ___ | \ 5 /|| | 4 ___ | \ 5 /| 4 ___ | \ 5 /|| |x + \/ 7 *sin|-----------| + I*\/ 7 *cos|-----------||*|x + \/ 7 *sin|-----------| - I*\/ 7 *cos|-----------||*|x + - \/ 7 *sin|-----------| + I*\/ 7 *cos|-----------||*|x + - \/ 7 *sin|-----------| - I*\/ 7 *cos|-----------|| \ \ 2 / \ 2 // \ \ 2 / \ 2 // \ \ 2 / \ 2 // \ \ 2 / \ 2 //
$$\left(x + \left(\sqrt[4]{7} \sin{\left(\frac{\operatorname{atan}{\left(\frac{\sqrt{3}}{5} \right)}}{2} \right)} - \sqrt[4]{7} i \cos{\left(\frac{\operatorname{atan}{\left(\frac{\sqrt{3}}{5} \right)}}{2} \right)}\right)\right) \left(x + \left(\sqrt[4]{7} \sin{\left(\frac{\operatorname{atan}{\left(\frac{\sqrt{3}}{5} \right)}}{2} \right)} + \sqrt[4]{7} i \cos{\left(\frac{\operatorname{atan}{\left(\frac{\sqrt{3}}{5} \right)}}{2} \right)}\right)\right) \left(x + \left(- \sqrt[4]{7} \sin{\left(\frac{\operatorname{atan}{\left(\frac{\sqrt{3}}{5} \right)}}{2} \right)} + \sqrt[4]{7} i \cos{\left(\frac{\operatorname{atan}{\left(\frac{\sqrt{3}}{5} \right)}}{2} \right)}\right)\right) \left(x + \left(- \sqrt[4]{7} \sin{\left(\frac{\operatorname{atan}{\left(\frac{\sqrt{3}}{5} \right)}}{2} \right)} - \sqrt[4]{7} i \cos{\left(\frac{\operatorname{atan}{\left(\frac{\sqrt{3}}{5} \right)}}{2} \right)}\right)\right)$$
(((x + 7^(1/4)*sin(atan(sqrt(3)/5)/2) + i*7^(1/4)*cos(atan(sqrt(3)/5)/2))*(x + 7^(1/4)*sin(atan(sqrt(3)/5)/2) - i*7^(1/4)*cos(atan(sqrt(3)/5)/2)))*(x - 7^(1/4)*sin(atan(sqrt(3)/5)/2) + i*7^(1/4)*cos(atan(sqrt(3)/5)/2)))*(x - 7^(1/4)*sin(atan(sqrt(3)/5)/2) - i*7^(1/4)*cos(atan(sqrt(3)/5)/2))
Unión de expresiones racionales
[src]
2 / 2\ 7 + y *\5 + y /
$$y^{2} \left(y^{2} + 5\right) + 7$$
7 + y^2*(5 + y^2)