Question

y²=2x-x² 怎么解出x=1+根号下(1-y²)

Answer 1

两边同时减1然后配方可得y^2-1 = -(1-x)^2, -> x-1 = 根号下(1-y²)
-> x=1+根号下(1-y²)

Answer 2

y²=2x-x²
y²-1=2x-x²-1
y²-1=-(x²-2x+1)
x²-2x+1=1-y²
(x-1)²=1-y²
x-1=±√(1-y²)
x=1±√(1-y²)