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Homework Help: What is value of tan[theta]

  1. Jul 3, 2010 #1
    tan.jpg

    in above image what is value of tan[theta].
    a)y/y+2x b)x/x+y c)y/y+x d)y/x

    This is not Home work! this question belongs to entry test.Which I
    can not solve so please do not give hints.
     
    Last edited: Jul 3, 2010
  2. jcsd
  3. Jul 3, 2010 #2

    D H

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    Re: tan

    This looks like homework.

    What do you think? The primary purpose of this site is to help students do their homework. We do not do it for you. Please show some work.
     
  4. Jul 3, 2010 #3
    Re: tan

    Hint:
    What is [tex]tan(x+\pi/4)[/tex]
     
    Last edited by a moderator: Jul 3, 2010
  5. Jul 3, 2010 #4
    Re: tan

    What sort of hint is that?
     
    Last edited by a moderator: Jul 3, 2010
  6. Jul 3, 2010 #5
    Re: tan

    This forum is not for lazy students who don't want to do their homework and we are not supposed to do it for them. So I gave a hint only. With that hint you can solve the problem without any thought about geometry. It's a 4 line mathematical rearrangement.
     
  7. Jul 3, 2010 #6

    HallsofIvy

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    Re: tan

    It's and excellent one! I will admit that for a moment I forgot that the smaller right triangle had both legs of length x:blushing:.
     
  8. Jul 4, 2010 #7
    Re: tan

    Gerenek, from your hint, I found the answer using the formula for tan(α+β). Is this an acceptable way to go about it? It took me than four steps...
     
  9. Jul 4, 2010 #8
    Re: tan

    My solution was both general and intuitive. It helps in understanding how & why. The insight gained will be useful in the real world.

    The proverbial fishing pole.
    The solution based on the little triangle being isosceles won't work if it isn't.
     
  10. Jul 4, 2010 #9
    Re: tan

    There is nothing intuitive about the need for new sketches and a length derivation. Also you fail the exam by running out of time if you solve the tasks much more generally than needed.
     
  11. Jul 4, 2010 #10

    HallsofIvy

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    Re: tan

    What solution? Your entire contribution to this thread was "What sort of hint is that?"


    In this problem it is. Gerunuk gave a hint to solve this problem.
     
  12. Jul 4, 2010 #11
    Re: tan

    It got deleted in exchange for an infraction.
     
  13. Jul 4, 2010 #12

    eumyang

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    Re: tan

    Hints are all you'll get here, I'm afraid. If this question is from an entrance exam, and a student doesn't know how to do problems like these, then he/she shouldn't belong to the program/school/course he/she is entering? :confused:

    Gerenuk's hint is excellent. Do you know your trigonometric identities?

    It took me 6 lines, not 4, but I tend to write more steps than probably what is necessary. :blushing:


    69
     
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