直线y=kx+1(k∈R)与椭圆
+=1恒有公共点,则m的取值范围是( )
A. [1,5)∪(5,+∞)
B. (0,5)
C. [1,+∞)
D. (1,5)
人气:167 ℃ 时间:2020-03-27 06:01:19
解答
联立y=kx+1x25+y2m=1,消去y得到(m+5k2)x2+10kx+5-5m=0,(m>0,m≠5)∵直线y=kx+1(k∈R)与椭圆x25+y2m=1恒有公共点,∴△≥0,即100k2-20(1-m)(m+5k2)≥0,化为m2+5mk2-m≥0,∵m>0,∴m≥-5k2+1,∵...
推荐
猜你喜欢
- Helen's parents working in China,her father is a teacher and her mother is a lawyer,Helen was born in the United States.
- 在三棱锥P-ABC中,面PAB垂直于面ABC,AB垂直于BC,AP垂直于PB,求证面PAC垂直于面PBC
- 用禁锢 器宇 鹤立鸡群 颔首低眉写一句话,不要“在封建文化的禁锢之下,黄宗羲器宇轩昂,在一众只肯埋首故
- He always gets to school—than his deskmate Bill.
- 某种细菌每经过20分钟便由1个分裂成2个,那么经过2小时后细菌有1个分裂成?个
- Sio2与C反应式?
- sin5π和cos5π等于多少
- 有甲乙两桶水,甲是乙的5倍,如果甲给乙倒入20千克后,两桶相等,甲乙两桶原来各有多少水?