题目
(a) Find the coordinates of the points of intersection of the curve and the line .
(b) Hence, solve .
题目中文翻译
(a) 求曲线 与直线 的交点坐标。
(b) 由此,解不等式 。
原卷通用作答要求
Answer all questions. You should use a calculator where appropriate.
You must show all necessary working clearly; no marks will be given for unsupported answers from a calculator.
Give non-exact numerical answers correct to 3 significant figures, or 1 decimal place for angles in degrees, unless a different level of accuracy is specified in the question.
请回答所有题目。适当时应使用计算器。必须清楚展示所有必要的计算过程;仅给出计算器答案而没有过程,不予评分。除非题目另有精度要求,非精确数值答案保留 3 位有效数字,以度为单位的角度保留 1 位小数。
解答
(a)
解法一
思路
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交点的纵坐标相同,所以令两式相等。先求横坐标,再用直线回代。
答题过程
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Equating the two expressions gives
Thus or . Substituting into gives the points and .
(b)
解法一
思路
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用 (a) 的两个交点作为分界。用曲线高度减去直线高度,所得二次式应小于或等于零。
答题过程
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The inequality is equivalent to . This holds between the roots, including the endpoints, so .