问题补充:
已知二次函数Y=AX+BX+C的图象以X=1为对称轴,且过点《-1,0》和《0,3》求此函数图象怎么写啊,拜托各位高手帮忙,谢谢
答案:
已知对称轴,可设:y = m(x - 1)^2 + n
将《-1,0》和《0,3》代入得方程组:
0 = m(-1 - 1)^2 + n
3 = m(0 - 1)^2 + n
即4m + n = 0
m + n = 3则m = -1n = 4所以,y = -(x - 1)^2 + 4 = -x^2 + 2x +3
时间:2019-12-10 16:08:32
已知二次函数Y=AX+BX+C的图象以X=1为对称轴,且过点《-1,0》和《0,3》求此函数图象怎么写啊,拜托各位高手帮忙,谢谢
已知对称轴,可设:y = m(x - 1)^2 + n
将《-1,0》和《0,3》代入得方程组:
0 = m(-1 - 1)^2 + n
3 = m(0 - 1)^2 + n
即4m + n = 0
m + n = 3则m = -1n = 4所以,y = -(x - 1)^2 + 4 = -x^2 + 2x +3