配套习题- 待定系数法确定二次函数解析式 -【青果学院】

1/5单选题

难度：

1.如图，抛物线的函数表达式是（　　）

A	y=x²-x+2
B	y=x²+x+2
C	y=-x²-x+2
D	y=-x²+x+2

正确答案：RA==

6Kej77ya5qC55o2u6aKY5oSP77yM6K6+5LqM5qyh5Ye95pWw55qE6KGo6L6+5byP5Li6eT1heDxzdXA+Mjwvc3VwPitieCtj77yMPGJyPuaKm+eJqee6v+i/h++8iC0x77yMMO+8ie+8jO+8iDDvvIwy77yJ77yM77yIMu+8jDDvvInvvIw8YnI+5omA5LulPGltZyB3aWR0aD0xMTUgaGVpZ2h0PTgzIHNyYz0iaHR0cHM6Ly9wMS5xaW5nZ3VvLmNvbS9HMS9NMDAvNDkvMkMvckJBQ0UxUEl3NG1Sc0JEVUFBQUR3QmlWMS1VMzQ3LnBuZyI+PGJyPuino+W+l2E9LTHvvIxiPTHvvIxjPTLvvIw8YnI+6L+Z5Liq5LqM5qyh5Ye95pWw55qE6KGo6L6+5byP5Li6eT0teDxzdXA+Mjwvc3VwPit4KzIuIDxicj7mlYXpgIlELiA=

2/5单选题

难度：

2.已知二次函数的图象经过（1，0）、（2，0）和（0，2）三点，则该函数的解析式是（　　）

A	y=2x²+x+2
B	y=x²+3x+2
C	y=x²-2x+3
D	y=x²-3x+2

正确答案：RA==

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

3/5单选题

难度：

3.如果抛物线y=x²-6x+c-2的顶点到x轴的距离是3，那么c的值等于（　　）

A	8
B	14
C	8或14
D	-8或-14

正确答案：Qw==

6Kej77ya5qC55o2u6aKY5oSPPGltZyB3aWR0aD02OSBoZWlnaHQ9NDIgc3JjPSJodHRwczovL3AxLnFpbmdndW8uY29tL0cxL00wMC80OS8yQy9yQkFDRTFQSXc1Q1FrUUcwQUFBQ1NnTXpySVU3MzcucG5nIj49wrEzPGJyPuino+W+l2M9OOaIljE0LiA8YnI+5pWF6YCJQy4g

4/5单选题

难度：

4.

如果抛物线y=-x²+bx+c经过A（0，-2），B（-1，1）两点，那么此抛物线经过（　　）

A	第一、二、三、四象限
B	第一、二、三象限
C	第一、二、四象限
D	第二、三、四象限

正确答案：RA==

PHA+6Kej77ya4oi15oqb54mp57q/eT0teDxzdXA+Mjwvc3VwPitieCtj57uP6L+HQe+8iDDvvIwtMu+8ie+8jELvvIgtMe+8jDHvvInkuKTngrnvvIw8YnI+4oi0PGltZyBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzQ5LzJDL3JCQUNFMVBJdzViZ0t6ZzNBQUFDbGtkNTlwRTAyMS5wbmciIGRhdGEtY2tlLXNhdmVkLXNyYz0iaHR0cHM6Ly9wMi5xaW5nZ3VvLmNvbS9HMS9NMDAvNDkvMkMvckJBQ0UxUEl3NWJnS3pnM0FBQUNsa2Q1OXBFMDIxLnBuZyIgaGVpZ2h0PSI2MiIgd2lkdGg9IjExNSI+PGJyPuKItOivpeaKm+eJqee6v+eahOino+aekOW8j+aYr++8mnk9LXg8c3VwPjI8L3N1cD4tNHgtMj0t77yIeCsy77yJPHN1cD4yPC9zdXA+KzLvvIw8YnI+4oi06K+l5oqb54mp57q/55qE5byA5Y+j5ZCR5LiL77yM6aG254K55Z2Q5qCH5piv77yILTLvvIwy77yJ77yM5LiOeei9tOeahOS6pOeCueaYr++8iDDvvIwtMu+8ie+8jDxicj7iiLTor6Xmipvniannur/nu4/ov4fnrKzkuozjgIHkuInjgIHlm5vosaHpmZAuPGJyPuaVhemAiUQuPGJyPjwvcD4=

5/5单选题

难度：

5.若所求的二次函数图象与抛物线y=2x²-4x-1有相同的顶点，并且在对称轴的左侧，y随x的增大而增大，在对称轴的右侧，y随x的增大而减小，则所求二次函数的解析式为（　　）

A	y=-x²+2x-5
B	y=ax²-2ax+a-3（a＞0）
C	y=-2x²-4x-5
D	y=ax²-2ax+a-3（a＜0）

正确答案：RA==

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