2019年高考全国2卷理科数学及答案
1.题目:设集合A={x|x2-5x+6>0},B={x|x-1<0},则A∩B=?
答案:B.(-2,1)
2.题目:设z=-3+2i,则在复平面内z对应的点位于?
答案:B.第二象限
3.题目:已知AB=(2,3),AC=(3,t),BC=1,则ABBC=?
答案:C.2
4.题目:2019年1月3日嫦娥四号探测器成功实现人类历史上首次月球背面软着陆,我国航天事业取得又一重大成就,实现月球背面软着陆需要解决的一个关键技术问题是地面与探测器的通讯联系.为解决这个问题,发射了嫦娥四号中继星“鹊桥”,鹊桥沿着围绕地月拉格朗日L2点的轨道运行.L2点是平衡点,位于地月连线的延长线上.设地球质量为M1,月球质量为M2,地月距离为R,L2点到月球的距离为r,根据牛顿运动定律和万有引力定律,r满足方
程:M1M2/(M1+M2)=(R+r)2/r3,设α=3M2/(4M1+12M2),由于α的值很小,因此在近似计算中,则r的近似值为2(1+α)R/M2.
答案:B.M2R/2M1
5.题目:演讲比赛共有9位评委分别给出某选手的原始评分,评定该选手的成绩时,从9个原始评分中去掉1个最高分、1个最低分,得到7个有效评分.7个有效评分与9个原始评分相比,不变的数字特征是?
答案:B.平均数
6.若a>b,则……
答案:缺少信息,无法回答。
1.ln(a-b)。0
2.3a < 3b
3.a^3 - b^3.0
4.|a|。|b|
5.α and β are two planes。The XXX n for α to be parallel to β is:
A。α has infinitely many lines parallel to β.
2019高考数学答案
B。α has two intersecting lines parallel to β.
C。α and β are parallel to the same line.
6.The focus of the parabola y = 2px (p。0) is an ellipse with one focus at x^2/3p + y^2/p = 1.Then p =
A。8
B。3
C。4
D。2
7.The n that is dic with d π and XXXπ/2.π) is:
A。f(x) = |cos 2x|
B。f(x) = |sin 2x|
C。f(x) = cos |x|
D。f(x) = sin |x|
8.Given α ∈ (0.π/2)。if 2sin 2α = cos 2α + 1.then sin α =
A。5/5
B。5/5
C。3/3
D。25/5
9.Let F be the right focus of the hyperbola C: x^2/a^2 - y^2/b^2 = 1 (a。0.b。0)。O be the origin。and the circle with OF as diameter intersects the circle x^2 + y^2 = a^2 at points P and Q。If PQ = OF。then the XXX:
A。2
B。3
C。2
D。5
10.Let the n f(x) have the domain R。satisfy f(x+1) = 2f(x)。and f(x) = x(x-1) when x ∈ (0,1]。If f(x) ≥ - for all x ∈ (-∞。m]。then the range of m is:
A。(8/9.9758]
B。(-∞。8/9]
C。(-∞。9758]
D。(-∞。∞)
11.Fill in the XXX:
12.Fill in the XXX:
13.XXX XXX rate of all high-speed trains XXX:
14.If f(x) is an odd n and f(x) = -eax for x < 0.and f(ln2) = 8.then a =