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Algebra Difficulty 5.3 AIME, harder Find the answer

Three, (20 points) Solve the system of equations
{x22(x1)=y.y22(1y)=x. \left\{\begin{array}{l} \frac{x^{2}}{2(x-1)}=y . \\ \frac{y^{2}}{2(1-y)}=x . \end{array}\right.

Solution

Three, Solution Using the substitution method, we get
x=x44(x1)3+4(x1) x=\frac{x^{4}}{4(x-1)^{3}+4(x-1)} \text {. }

Rearranging gives
x(x2)(3x26x+4)=0 x(x-2)\left(3 x^{2}-6 x+4\right)=0 \text {, }

Solving this yields
x1=0,x2=2,x3=1+33i,x4=133i. \begin{array}{l} x_{1}=0, \\ x_{2}=2, \\ x_{3}=1+\frac{\sqrt{3}}{3} i, \\ x_{4}=1-\frac{\sqrt{3}}{3} i . \end{array}

Substituting into yy gives
y1=0,y2=2,y3=133i,y4=1+33i. \begin{array}{l} y_{1}=0, \\ y_{2}=2, \\ y_{3}=1-\frac{\sqrt{3}}{3} i, \\ y_{4}=1+\frac{\sqrt{3}}{3} i . \end{array}

Thus, there are 4 sets of solutions
{x1=0,y1=0;{x2=2,y2=2,{x3=1+33i,y3=133i;{x4=133i,y4=1+33i. \begin{array}{l} \left\{\begin{array}{l} x_{1}=0, \\ y_{1}=0 ; \end{array}\right. \\ \left\{\begin{array}{l} x_{2}=2, \\ y_{2}=2, \end{array}\right. \\ \left\{\begin{array}{l} x_{3}=1+\frac{\sqrt{3}}{3} i, \\ y_{3}=1-\frac{\sqrt{3}}{3} i ; \end{array}\right. \\ \left\{\begin{array}{l} x_{4}=1-\frac{\sqrt{3}}{3} i, \\ y_{4}=1+\frac{\sqrt{3}}{3} i . \end{array}\right. \end{array}

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.