He is ________ to make money to help his parents live a better life.
A:old enough
B:enough old
C:young enough
D:enough young
已知A、B、C是抛物线y2=2px(p>0)上三个不同的点,且AB⊥AC.
(Ⅰ)若A(1,2),B(4,﹣4),求点C的坐标;
(Ⅱ)若抛物线上存在点D,使得线段AD总被直线BC平分,求点A的坐标.
对于平行线,我们有这样的结论:如图1,AB∥CD,AD,BC交于点O,则AODO=BOCO.
请利用该结论解答下面的问题:
如图2,在△ABC中,点D在线段BC上,∠BAD=75°,∠CAD=30°,AD=2,BD=2DC,求AC的长.
已知函数f(x)=ax2+2x+c,且f(x)>0的解集为{x|x≠﹣1a}.
(1)求f(2)的取值范围;
(2)在f(2)取得最小值时,若对于任意的x∈2,+∞),f(x)+2≥mf′(x)恒成立,求实数m的取值范围.