【基础级练习题63】
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+ p, M8 i! }) F( i8 f; V; _求: 7 w' E3 p0 w l* n! K' G
1. A弧之弧长为何?
+ G a( ]1 Z$ |7 P4 N- J* ^# T (A) 39.2699 (B) 39.2969 (C) 39.2996 1 ` K% l: U2 f# X8 ?) _# U/ H
2. B弧之弧长为何? , G% n% i. w! d$ y' X& u& D
(A) 78.5398 (B) 78.5893 (C) 78.5938
+ d, j; O4 Z" M* R% F3. C弧之弧长为何? ( Q8 O E6 ~: y* j8 o
(A) 41.0359 (B) 41.0593 (C) 41.0935 , D& z+ x5 U1 ^$ l% ]; ?- ~6 C
4. 剖面线区域之面积为何?
6 k/ U( M7 ]2 \9 c) Q" | (A) 2862.6778 (B) 2862.6787 (C) 2862.6877
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& w- U x: [% N: f1 }$ O【基础级练习题63】标准答案: / f0 u3 U7 K7 T6 U
1. A弧之弧长 = 39.2699,就是(A) 6 Z4 h: T }0 ]2 R3 z; g9 \; p
2. B弧之弧长 = 78.5398,就是(A) # l8 l) T( d. }9 o$ U, h6 d: m
3. C弧之弧长 = 41.0593,就是(B) " {) D) N4 W% `) p- i4 V
4. 剖面线区域之面积 = 2862.6877,就是(C)
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" e$ z3 J9 @/ d0 j& L2 v' B【基础级练习题63】解题思路:
6 x' g9 ~: D/ ~$ }4 A本题的关键点,是利用各圆心画与圆相切的圆,有相交相切圆,由包含相切圆。还有就 3 W; L! j. p7 B7 N1 v4 z
是圆弧的偏移,虽比较简单,但还是很值得一练。( R+ P2 @# n+ Y! c5 V$ X2 `# a% f
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