直线y=x-2和抛物线y=ax^2+bx+c的两个交点分别在x轴和y轴上交点是(0,-2),(2,0)
将他们代入抛物线y=ax^2+bx+c,
抛物线的对称轴是x=3,-b/2a=3c=-24a+2b+c=0a=-1/4b=3/2
抛物线的解析式y=-1/4(x-3)^2+1/4
=-1/4(x^2-6x+9)+1/4
=-x^2/4+3x/2-2
直线y=x-2和抛物线y=ax^2+bx+c的两个交点分别在x轴和y轴上交点是(0,-2),(2,0)
将他们代入抛物线y=ax^2+bx+c,
抛物线的对称轴是x=3,-b/2a=3c=-24a+2b+c=0a=-1/4b=3/2
抛物线的解析式y=-1/4(x-3)^2+1/4
=-1/4(x^2-6x+9)+1/4
=-x^2/4+3x/2-2