Question

对于函数x²＋y²＋z²＝2z,确定z＝f（x,y）

Answer 1

z^2-2z+1=1-x^2-y^2

(z-1)^2=1-x^2-y^2

z=1+√(1-x^2-y^2)或z=1-√(1-x^2-y^2)

z=f(x,y)=1+√(1-x^2-y^2)或z=f(x,y)=1-√(1-x^2-y^2)