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讨论下面两个命题: 命题1 在圆内,不平分弦而垂直于弦的直线不过圆心且不平分这弦所对的弧. 命题2 在圆内,不平分弦而过圆心的直线不垂直于这弦且不平分这弦所对的弧. 它们都是真命题且相互联系,但能否以证明命题2代替证明命题1呢?证明命题2是否是用反证法对命题1的证明?命题2是否是命题1的逆否命题?这些都是中学生不大重视且
The following two propositions are discussed: Proposition 1 In a circle, a straight line that is uneven and perpendicular to the string is not a circle, but does not bisect the arc to which the string belongs. Proposition 2 Within a circle, a straight line that is uneven and that is over the center is not perpendicular to This string does not bisect the arc to which this string belongs. They are true propositions and relate to each other, but can we substitute Proof Proposition 2 in place of Proposition 1? Is proposition 2 proof of proposition 1 with counterevidence? Proposition 2 Is the inverse proposition of proposition 1, these are all secondary students do not pay much attention and