Circle C and line k lie in the xy-plane. If circle C is centered at the origin and has radius 1, does line k intersect circle C ?
(1) The x-intercept of line k is greater than 1.
(2) The slope of line k is ~$-\frac{1}{10}$~ .
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
两个条件联立 求出直线y=1/10x+b的b的范围 再利用点到直线的距离公式 求出距离d 大于某个数 而这个数不到1 因此不充分
求一下x=1时直线与圆的相交情况,因为斜率已经固定,把求出来的直线向x>1的方向平移就能看出x>1后,直线与圆的相交情况。
啊,是greater啊……算了一下等于1的时候是俩交点,平移的话可能相交可能相离
啊,是greater啊……算了一下等于1的时候是俩交点,平移的话可能相交可能相离
截距不是距离,有正有负
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联立方程 直线和圆的方程,接的△<0.4,既可能有解也可能无解,无法确定,选E