题干

[选修4-4:坐标系与参数方程]

已知在直角坐标系xOy中,曲线C的参数方程为 {x=2cosϕy=2+2sinϕ (φ为参数),在极坐标系(与直角坐标系xOy取相同的长度单位,且以原点O为极点,以x轴正半轴为极轴)中,直线l的方程为ρcos(θ﹣

π
4
)=2 2

(Ⅰ)求曲线C在极坐标系中的方程;

(Ⅱ)求直线l被曲线C截得的弦长.

上一题 下一题 0.0难度 选择题 更新时间:2019-05-18 10:46:56

答案(点此获取答案解析)

解:(Ⅰ)曲线C的参数方程为 {x=2cosϕy=2+

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    What Theresa Loe is doing proves that a large farm isn't a prerequisite for a modern grow-your-own lifestyle. On a mere 1/10 of an acre in Los Angeles, Loe and her family grow, can(装罐)and preserve much of the food they consume.

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