已选分类
理学数学
试题题型
单选题问N为多少? (1)N只有2和3两个质因子 (2)N的因子个数为12。 (A) 条件(1)充分，但条件(2)不充分． (B) 条件(2)充分，但条件(1)不充分． (C) 条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分． (D) 条件(1)充分，条件(2)也充分． (E) 条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．
单选题The Binary Ice Cream Shoppe sells two flavors, vanilla and chocolate. On Friday, the ratio of vanilla cones sold to chocolate cones sold was 2 to 3. If the store had sold 4 more vanilla cones, the ratio of vanilla cones sold to chocolate cones sold would have been 3 to 4. How many vanilla cones did the store sell on Friday? (A) 32 (B) 35 (C) 42 (D) 48 (E) 54
单选题有一组数是0，9，5，X，Y，其中X，Y是正数，问这组数的值域(range)是多少? (1)X+Y=9 (2)X+Y=1 (A) 条件(1)充分，但条件(2)不充分． (B) 条件(2)充分，但条件(1)不充分． (C) 条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分． (D) 条件(1)充分，条件(2)也充分． (E) 条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．
单选题设0＜P(A)＜1，0＜P(B)＜1，，则下式中不成立的是______。A．B．P(AB)=0C．D．
单选题A certain grocery purchased x pounds of produce for p dollars per pound. If y pounds of the produce had to be discarded due to spoilage and the grocery sold the rest for s dollars per pound, which of the following represents the gross profit on the sale of the produce?
单选题下列函数中，非奇非偶的函数是______．
单选题
单选题设三个实数a，b，c在数轴上的位置如图，则|a|+|b|+|c|-|a+b|+|b+c|-|c-a|=______．A．a-b+cB．a+b-cC．a+b+cD．a-b-c
单选题设函数，讨论函数f(x)的间断点，其结论为______。A.不存在间断点B.存在间断点x=1C.存在间断点x=0D.存在间断点x=-1
单选题A student had an average of 86 for three tests. If the student's highest test score was 2a, what was the average of the student's two lowest scores? (A) 129-2a (B) 258-2a (C) 129-a (D) 258+2a (E) 258-a
单选题A car dealer who gives a customer a 20 percent discount on the list price of a car still realizes a net profit of 25 percent of cost. If the dealer's cost is $4800, what is the usual list price of the car?
单选题(1)X＞0(2)X＜1(A)条件(1)充分，但条件(2)不充分．(B)条件(2)充分，但条件(1)不充分．(C)条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分．(D)条件(1)充分，条件(2)也充分．(E)条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．
单选题设X～N(-1，2)，Y～N(1，3)，且X与Y相互独立，则X+Y～______。
A.N(1，8)
B.N(1，14)
C.N(0，5)
D.N(0，40)
单选题Ifthespacesbetweentheletteredpointsinthefigureaboveareallequal,thenisequaltowhichofthefollowing?(A)PS-QR(B)QR-QS(C)PR(D)QT(E)ST
单选题设函数f(x)对任意z均满足f(1+x)=af(x)，且f′(0)=b，其中a，b为非零常数，则______. A．f(x)在x=1处不可导 B．f(x)在x=1处可导，且f′(1)=a C．f(x)在x=1处可导，且f′(1)=b D．f(x)在x=1处可导，且f′(1)=ab
单选题的连续区间是______．A．(-∞，1)∪(1，2)∪(2，+∞)B．(-∞，1)∪(1，+∞)C．(-∞，1)∪(1，2)D．(-∞，2)∪(2，+∞)
单选题In a certain company, the ratio of the number of women employees to the number of men employees is 3 to 2. If the total number of employees is 240, then how many of the employees are men?
单选题设α1，α2是齐次线性方程组Ax=0的基础解系，β1，β2是对应非齐次线性方程组Ax=b的两个不同的解，k1，k2为任意常数，则Ax=b的通解是______。A．B．C．D．
单选题约等于几?
单选题 1 2 3 4 5 6 7 -2 -4 -6 -8 -10 -12 -14 3 6 9 12 15 18 21 -4 -8 -12 -16 -20 -24 -28 5 10 15 20 25 30 35 -6 -12 -18 -24 -30 -36 -42 7 14 21 28 35 42 49 What is the sum of the integer in the table above? (A) 28 (B) 112 (C) 336 (D) 448 (E) 784