y=ax平方+bx+c转换为y=a(x-h)+k

问题描述:

y=ax平方+bx+c转换为y=a(x-h)+k

ax^2+bx+c
=a(x^2+bx/a)+c
=a(x^2+bx/a+(b/2a)^2)+c-a(b/2a)^2
=a(x+b/2a)^2+(4ca-b^2)/4a