设函数f(x)=1-x^2在区间(,)
已知a,b为常数，时为等价无穷小，求a,b.
TheinteractionsbetweenChinaandtheUSwillsurelyhaveasignificant_______on.peaceandstabilityintheAsia.—Pacificregionandtheworldasawhole.
已知离散型随机变量X的概率分布为
X10203040
P a
(1)求常数a;(2)求X的数学期望EX.
直线y=kx与圆x2+y2-4x+3=0有两个交点
(1)√3/3
