[計量] 兩題PS..拜託了!
1.這題有圖~麻煩開啟下面連結
http://www.wretch.cc/album/show.php?i=kayfire&b=120&f=1051007489&p=0
In the circle above, PQ is parallel to diameter OR, and OR has length 18.
what is the length of minor arc PQ?
A.2π
B.9π/4
C.7π/2
D.9π/2
E.3π
ans:A
這題整個不會算 囧 可以請高手解惑嗎??
第一題來自解XDDDD 剛剛在網路上找到影片可以解這題~給也不會的人參考一下
主要是用圓周角跟圓心角的定理
關於定理可以參考下面的影片~看完應該就會了^^
http://www.powercam.cc/show.php?id=629&ch=1&fid=9
2.If x is positive, which of the following could be the correct ordering
of 1/x, 2x, and x^2?
I. x^2 < 2x <1/x
II. x^2 < 1/x < 2x
III. 2x < x^2 <1/x
A.none
B.I only
C.III only
D.I & II only
E.I & II & III
ans:D
我對這題的疑問是,他只說x>0,若x=1或2...則上述三個式子沒有任何一個成立
或x為大於2的整數也不會等於上面任何一個式子
為什麼不能選none呢?
麻煩大家幫個忙了~謝謝^^
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◆ From: 111.250.16.139
※ 編輯: kayfire 來自: 111.250.16.139 (10/24 18:33)
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