经过M(2,1)作直线L交双曲线于A、B两点,且M为AB的中点, (1)求直线L的方程;(7分) (2)求线段AB的长。 (6分) 答案:(本题满分13分) 解(1)设,则,由,得所以 直线L的方程为 (2) 把代入消去得 所以,从而得
Gutter oil is illegally recycled cooking oil, ________ contains chemicals that are harmful to the human body and can even cause cancer.
[ ]
A.
it
B.
which
C.
where
D.
that