ʱ : һ 中考第一轮复习第12讲《二次函数》专题训练含答案 - 百度文库ϿʼĶ
(4ͼ)
Amnkh Bmnkh Cmnkh Dmnkh
5ͼ֪κyx2bxcͼA(1,0)B(12)ͼxһΪCACΪ__________
(5ͼ)
6yax2bxcϲֵĺxyĶӦֵ±
x y 2 0 1 4 0 6 1 6 2 4 ϱ֪˵ȷ__________(д) xһΪ(3,0) ںyax2bxcֵΪ6
1
ߵĶԳֱx
2
ڶԳ࣬yx
7yx2bxcͼͼʾƽ2λƽ3λƽƺĽʽΪ__________
82011곤εش飬ΪգijƶũͶʹ豸IJ취й͡Ϳ豸ͶʵĽĶȴ±ʾĺӦϵ.
9 ҳ 13 ҳ
(1)ֱy1y2ĺʽ
(2)һũͬʱԢ͡豸Ͷ10Ԫһܻķ˷ܻõ
9ͼ֪κL1yx24x3xύAB(AڵB)yύڵC.
(1)дκL1ĿڷԳͶꣻ (2)оκL2ykx24kx3k(k0)
дκL2κL1йͼͬʣ
ֱy8kL2EF㣬߶EFijǷ仯ᣬEFijȣᣬ˵ɣ
ο
ѧر֪ʶ 1C
2D x㣬b24ac0yύ(0,0)(0,1)֮䣬0c1(2)
bb
ߣ1ࣼ1a02ab2ab0
2a2a
x1ʱyabc0ѡD.
33 ⣬m272m30m3. 4yx21
5yx22x1(𰸲Ψһ) ̽㷽 ͨ1D
ͨ2C ߿ϣa0
10 ҳ 13 ҳ
yύڸᣬc0
ԳyҲ࣬abţb0abc0. ͼ֪x1ʱy0 1
abc0.Գֱx
3
b1
࣭2a3b0
2a3
??abc>05?cb0.
2
?2a3b0?
֡b0c4b0.ȷĽ4
ͨ3A Ϊκyx2ƽ1λy(x1)2ƽ2λy(x1)22ѡA.
ͨ4⣺(1)xyԳƣߵĶԳἴΪyᣮ 6m2࣭0.m6.
1?2??2?֡߿£m30m3.m6. (2)m6
1
ߵĹϵʽΪyx23Ϊ(0,3)
2ͨ5⣺(1)(107x) (126x) (2)y(126x)(107x)2x. (3)w2(1x)(2x)2x22x4 w2(x0.5)24.5. ߣ20,0x11
൱x0.5ʱw4.5(Ԫ)
𣺵xΪ0.5ʱ4.5Ԫ Ʒ俼
1B ߶κyax2bx1Ķڵһޣ Ҿ(1,0) ab10a0b0.
ab10õb1b00b1٣ ba10õa1a0 ࣭1a0.
ɢ٢ڵã1ab1c1 õ0ab12 0t2.
2C ߶κͼ£a0.
b
߶Գx0b0.
2a߶κͼԭ㣬c0.
a
һκybxcڶҾԭ㣬yλڵڶޣ
x
11 ҳ 13 ҳ
ѡC.
3yx2x2 Ϊƽ2λyֵԭĻϼ2ߵıʽyx2x2.
41x3 Ϊκͼxֱ(1,0)(3,0)ͼ֪y0ʱԱxȡֵΧǣ1x3.
5⣺(1)⣬
(12)2m0m1y(x2)21. x0ʱy(02)213C(0,3) ߵBCֱx2ԳƣB(4,3)
???0kb?k1
??
???34kb?b1.
yx1.
(2)xȡֵΧ1x4.
6⣺(1)PP(1,3)xԳƣ PΪ(13)
a?131?2c0??ya(x1)2cA(130)P(13)?
?a?11?2c3?
??a1
?
c3.??
ߵĽʽΪy(x1)23yx22x2. (2)CDƽxᣬP(1,3)CDϣ CDΪ3
(x1)233x116x216 CDֱΪ(163)(163) CD26
ࡰWͼĸ(CD)ıȣϰԤ 1A 2C
3D ⣬224(k3)0k30k4k3ѡD. 4A
326
6
(Լ0.612 4) 4
???1bc0?b1
53 ߰A(1,0)B(12)yxbxc??y
???1bc2?c2
2
x2x2x2x20x11x22CΪ(2,0)AC3.
6٢ۢ ͼ֪x0ʱy6x1ʱy6ߵĶԳֱx
11
ȷxһΪ(2,0)Գֱxxһ22
1
Ϊ(3,0)ȷͼ֪ڶԳ࣬yxȷxʱy
2ȡֵڴ
12 ҳ 13 ҳ