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Homework Help: Given that (csc a) = (sec0.75), 'a' lies in the second quadrant, determine angle 'a'

  1. Feb 11, 2009 #1
    1. The problem statement, all variables and given/known data

    Given that (csc a) = (sec0.75) and that 'a' lies in the second quadrant, determine the measure of angle 'a', to two decimal places.

    2. Relevant equations

    reciprocal and quotient identities.

    3. The attempt at a solution

    I only got as far as:

    1/sin(a) = 1/cos(0.75)

    The answer in the back of the book is 2.32

    Can anyone guide me towards the light? thanks in advance!
     
  2. jcsd
  3. Feb 11, 2009 #2

    HallsofIvy

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    Science Advisor

    Re: Given that (csc a) = (sec0.75), 'a' lies in the second quadrant, determine angle

    Well, it is not difficult to find that cos(.75)= .7317 using a calculator and , again using a calculator, that sin(a)= .7317 for a= .8208. Of course, that is the "principal root", less than [itex]\pi/2[/itex]. Since a is in the second quadrant, a= [itex]\pi[/itex]- .8208= 2.3208
     
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