GRE
$$C_k$$
$$\frac{2k^2-1}{k+k}$$
3 times the number of elements in V
The number of elements in the set R∪S∪T
x
y
p
q+r+s
The amount of time that it takes machines K, L, and M, working simultaneously at their respective constant rates, to produce 100 units of product Z
1 hour
n
16
The perimeter of quadrilateral ABCD
8r
$$x$$
$$90$$
$$d$$
$$k^2$$
The probability that w will precede x in the sequence
$$\frac{1}{2}$$
$$p$$
$$r$$
25000 +道题目
236本备考书籍