-Do you know where your brother is,Mark?
-Sorry.I __________ about a question and didn't hear what you had said.
was thinking
will think
am thinking
was thought
若点在圆外,则的取值范围是()
如图,在三棱锥中,若,,是的中点,则下列命题中正确的是()
设函数,则()
与双曲线有共同的渐近线,且经过点的双曲线的方程为()
双曲线的离心率大于的充分必要条件是()