怎么把y=a(x-h)x^2+k怎么化成y=ax^2+bx+c的形式?怎么把y=a(x-h)x^2+

网友回答

y=a(x-h)²+k
=a(x²-2hx+h²)+k
=ax²-2ahx+(ah²+k)
x轴上y=0
所以横坐标就是y=ax²+bx+c=0的解
假设是x1,x2
则和x轴交点是(x1,0)和(x2,0)
y轴上x=0
则y=0+0+c
所以和y轴交点是(0,c)
======以下答案可供参考======
供参考答案1:
y'=2f(x)*f'(x)+f'(x²)*(x²)'
=2f(x)*f'(x)+2xf'(x²)
所以y''=2f'(x)*f'(x)+2f(x)*f''(x)+2f'(x²)+2xf''(x²)*(x²)'
=2[f'(x)]²+2f(x)*f''(x)+2f'(x²)+4x²f''(x²)