Question 19
(a) Solve over the real numbers: $(x^2-2x+2)^2+(x-1)(3x^2-10x+10)=0$.
(b) Positive integers $x,y,z$, with $x\ne y$, satisfy $x^2+y^2+z^2=189$ and $\dfrac{x}{y}=\dfrac{x^2+z^2}{y^2+z^2}$. Find $xyz$.
(b) Positive integers $x,y,z$, with $x\ne y$, satisfy $x^2+y^2+z^2=189$ and $\dfrac{x}{y}=\dfrac{x^2+z^2}{y^2+z^2}$. Find $xyz$.