2x^2+3y^2 equation
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The solution
Detail solution
This equation is of the form
a*y^2 + b*y + c = 0 A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
y 1 = D − b 2 a y_{1} = \frac{\sqrt{D} - b}{2 a} y 1 = 2 a D − b y 2 = − D − b 2 a y_{2} = \frac{- \sqrt{D} - b}{2 a} y 2 = 2 a − D − b where D = b^2 - 4*a*c - it is the discriminant.
Because
a = 3 a = 3 a = 3 b = 0 b = 0 b = 0 c = 2 x 2 c = 2 x^{2} c = 2 x 2 , then
D = b^2 - 4 * a * c = (0)^2 - 4 * (3) * (2*x^2) = -24*x^2 The equation has two roots.
y1 = (-b + sqrt(D)) / (2*a) y2 = (-b - sqrt(D)) / (2*a) or
y 1 = 6 − x 2 3 y_{1} = \frac{\sqrt{6} \sqrt{- x^{2}}}{3} y 1 = 3 6 − x 2 y 2 = − 6 − x 2 3 y_{2} = - \frac{\sqrt{6} \sqrt{- x^{2}}}{3} y 2 = − 3 6 − x 2
Vieta's Theorem
rewrite the equation
2 x 2 + 3 y 2 = 0 2 x^{2} + 3 y^{2} = 0 2 x 2 + 3 y 2 = 0 of
a y 2 + b y + c = 0 a y^{2} + b y + c = 0 a y 2 + b y + c = 0 as reduced quadratic equation
y 2 + b y a + c a = 0 y^{2} + \frac{b y}{a} + \frac{c}{a} = 0 y 2 + a b y + a c = 0 2 x 2 3 + y 2 = 0 \frac{2 x^{2}}{3} + y^{2} = 0 3 2 x 2 + y 2 = 0 p y + q + y 2 = 0 p y + q + y^{2} = 0 p y + q + y 2 = 0 where
p = b a p = \frac{b}{a} p = a b p = 0 p = 0 p = 0 q = c a q = \frac{c}{a} q = a c q = 2 x 2 3 q = \frac{2 x^{2}}{3} q = 3 2 x 2 Vieta Formulas
y 1 + y 2 = − p y_{1} + y_{2} = - p y 1 + y 2 = − p y 1 y 2 = q y_{1} y_{2} = q y 1 y 2 = q y 1 + y 2 = 0 y_{1} + y_{2} = 0 y 1 + y 2 = 0 y 1 y 2 = 2 x 2 3 y_{1} y_{2} = \frac{2 x^{2}}{3} y 1 y 2 = 3 2 x 2
___ ___
\/ 6 *im(x) I*\/ 6 *re(x)
y1 = ----------- - -------------
3 3
y 1 = − 6 i re ( x ) 3 + 6 im ( x ) 3 y_{1} = - \frac{\sqrt{6} i \operatorname{re}{\left(x\right)}}{3} + \frac{\sqrt{6} \operatorname{im}{\left(x\right)}}{3} y 1 = − 3 6 i re ( x ) + 3 6 im ( x )
___ ___
\/ 6 *im(x) I*\/ 6 *re(x)
y2 = - ----------- + -------------
3 3
y 2 = 6 i re ( x ) 3 − 6 im ( x ) 3 y_{2} = \frac{\sqrt{6} i \operatorname{re}{\left(x\right)}}{3} - \frac{\sqrt{6} \operatorname{im}{\left(x\right)}}{3} y 2 = 3 6 i re ( x ) − 3 6 im ( x )
y2 = sqrt(6)*i*re(x)/3 - sqrt(6)*im(x)/3
Sum and product of roots
[src]
___ ___ ___ ___
\/ 6 *im(x) I*\/ 6 *re(x) \/ 6 *im(x) I*\/ 6 *re(x)
----------- - ------------- + - ----------- + -------------
3 3 3 3
( − 6 i re ( x ) 3 + 6 im ( x ) 3 ) + ( 6 i re ( x ) 3 − 6 im ( x ) 3 ) \left(- \frac{\sqrt{6} i \operatorname{re}{\left(x\right)}}{3} + \frac{\sqrt{6} \operatorname{im}{\left(x\right)}}{3}\right) + \left(\frac{\sqrt{6} i \operatorname{re}{\left(x\right)}}{3} - \frac{\sqrt{6} \operatorname{im}{\left(x\right)}}{3}\right) ( − 3 6 i re ( x ) + 3 6 im ( x ) ) + ( 3 6 i re ( x ) − 3 6 im ( x ) )
/ ___ ___ \ / ___ ___ \
|\/ 6 *im(x) I*\/ 6 *re(x)| | \/ 6 *im(x) I*\/ 6 *re(x)|
|----------- - -------------|*|- ----------- + -------------|
\ 3 3 / \ 3 3 /
( − 6 i re ( x ) 3 + 6 im ( x ) 3 ) ( 6 i re ( x ) 3 − 6 im ( x ) 3 ) \left(- \frac{\sqrt{6} i \operatorname{re}{\left(x\right)}}{3} + \frac{\sqrt{6} \operatorname{im}{\left(x\right)}}{3}\right) \left(\frac{\sqrt{6} i \operatorname{re}{\left(x\right)}}{3} - \frac{\sqrt{6} \operatorname{im}{\left(x\right)}}{3}\right) ( − 3 6 i re ( x ) + 3 6 im ( x ) ) ( 3 6 i re ( x ) − 3 6 im ( x ) )
2
-2*(-im(x) + I*re(x))
----------------------
3
− 2 ( i re ( x ) − im ( x ) ) 2 3 - \frac{2 \left(i \operatorname{re}{\left(x\right)} - \operatorname{im}{\left(x\right)}\right)^{2}}{3} − 3 2 ( i re ( x ) − im ( x ) ) 2
-2*(-im(x) + i*re(x))^2/3