- A)坐标原点对称 (
- B)x轴对称 (
- C)y轴对称 (
- D)直线茗+Y=0对称
- 10
-
已知函数f(x)=㏒2(
- ax+
- b),若f(2)=2,f(3)=3,则( ) (A)a=1,b=-4 (B)a=2,b=-2 (
- C)a=4,b=3 (
- D)a=4,b=-4
- 11
-
等比数列{
- an}中,若a1 + a2 =30,a3 + a4 =120,则a5 + a6 =( ) (A)240 (
- B)480 (
- C)720 (
- D)960
- 12
-
若向量
- a=(x,2),
- b=(-2,4),且a,b共线,则x=( ) (A)-4 (B)-1 (
- C)1 (
- D)4
- 13
-
已知向量
- a=(3,-1),
- b=(5,y),若a∥b,则y=( ) (A)<img sr
- c="//img1.yq
- da.net/question-name/27/2c90619fc2d9846c42bcdd79253f5f.jpg" alt="" /> (B)<img src="//img1.yqda.net/question-name/38/1a9ec5d342139d8ffb03c08bd3d850.jpg" alt="" /> (C)<img src="//img1.yqda.net/question-name/b5/d
- A.2x-y-3=0
- B.y-2x-3=0
- C.x+2y-6=0
- D.2x+y-3=0
- A)6π (
- B)2π (
- C)π (
- D)<img src="//img1.yqda.net/question-name/e7/bd759b4a9d8cbb09ae961e669b9c4e.jpg" alt="" />
- A)-1 (
- B)<img sr
- c="//img1.yq
- da.net/question-name/7d/7058c62e8f7e2db1ca8666c4e05082.jpg" alt="" /> (C)1 (D)<img src="//img1.yqda.net/question-name/00/8e1a293932a291431cd1b74201a944.jpg" alt="" />
- 18
-
在△
- ABC中,
- b=7,
- c=5,a=4,这个三角形是( ) (A)锐角三角形 (B)直角三角形 (C)钝角三角形 (
- D)不能推判上述结论
- A)1 (
- B)-3 (
- C)3 (
- D)-4
- A.-3
- B.1
- C.3
- D.5
- A)y=-x<sup>3</sup> (
- B)y=x<sup>3</sup>-2 (
- C)<img src="//img1.yq
- da.net/question-name/68/cdacd60eadb4a734fdc58f8fe88bf0.jpg" alt="" /> (D)<img src="//img1.yqda.net/question-name/93/f3cc61f9c056f5c7918b301e2a4aa0.jpg" alt="" />
- A)3+log23 (
- B)1+2log23 (
- C)3 (
- D)4
- A)<img src="//img1.yqda.net/question-name/e4/70006
- bcfa58054841b70812f1f6243.jpg" alt="" /> (B)<img sr
- c="//img1.yq
- da.net/question-name/32/3eb1e4b52c66659bb3e4414cd2eb7e.jpg" alt="" /> (C)<img src="//img1.yqda.net/question-name/9b/ee08d11f57a06dd1906faff7b10b16.jpg" alt="" /> (D)<img src="//img1.yqda.net/question-name/92/a
- A)x2-6 (
- B)x2-5 (
- C)x2-2x-6 (
- D)x2-2x-5