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Question:

fairydrink
fairydrink
Student
High School - 10th Grade

Which is the biggest element of the set {cos 1, cos 2, cos3}?

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Posted by fairydrink on Wednesday April 22, 2009 at 6:18 AM and tagged with element, math, set.

Answers:

  1. giorgiana1976
    giorgiana1976 Teacher
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    eNotes Editor

    Because 1 is in the set (0,pi/2), meaning the first quadrant, where the function cosine is positive,then cos 1>0.

    Because 2 and 3 are in the set (pi/2,pi), then

    cos2 and cos 3<0, because of the fact that the set (pi/2,pi) does represent the second quadrant, where the values of cosine function are negative.

    So the biggest element is cos 1.

    We have to say that we've made the calculus knowing the approximate value of pi=3.1416...

    pi/2=3.14/2=1.07...

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    Posted by giorgiana1976 on Saturday May 30, 2009 at 2:13 PM