求出下列开口方向,对称轴,顶点坐标
y=2x²-4x+5
y=-x²+2x-3
1.
y=2x²-4x+5
=2x²-4x+2+3
=2(x²-2x+1)+3
=2(x-1)² +3
开口向上 ,对称轴 x=1 , 顶点坐标 (1,3)
2.
y=-x²+2x-3
=-x²+2x-1-2
=-(x²-2x+1)-2
=-(x-1)² -2
开口向下,对称轴 x=1 , 顶点坐标 (1,-2)
O(∩_∩)O~
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y=2x²-4x+5
y=-x²+2x-3
1.
y=2x²-4x+5
=2x²-4x+2+3
=2(x²-2x+1)+3
=2(x-1)² +3
开口向上 ,对称轴 x=1 , 顶点坐标 (1,3)
2.
y=-x²+2x-3
=-x²+2x-1-2
=-(x²-2x+1)-2
=-(x-1)² -2
开口向下,对称轴 x=1 , 顶点坐标 (1,-2)
O(∩_∩)O~