Trigonometric Equations...1

Discussion in 'Geometry and Trigonometry' started by nycmathguy, Mar 9, 2022.

  1. nycmathguy

    nycmathguy

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    Before continuing on in the polar world, I want to post four trigonometric equations that I recently found online. I don't understand the steps to solve such equations. The following trigonometric equations are not your typical trigonometric equations. When you have time, please provide a step by step solution to each problem. Thank you so much.

    Solve for x.

    sin x + cos x = 0
     
    nycmathguy, Mar 9, 2022
    #1
  2. nycmathguy

    MathLover1

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    sin x + cos x = 0
    sqrt(2) sin(x + π/4) = 0

    x = 1/4 (4 π n - π), n element Z

    [​IMG]
     
    MathLover1, Mar 10, 2022
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  3. nycmathguy

    nycmathguy

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    Sorry but I don't understand what you did here? Is there an algebraic way to solve the given equation for x?
     
    nycmathguy, Mar 10, 2022
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  4. nycmathguy

    MathLover1

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    this way:
    sin(x) + cos (x) =0........divide by cos (x)

    sin(x)/ cos (x) + cos (x)/cos (x) =0

    tan (x) + 1 =0

    tan (x) =-1

    x=tan^-1 (-1)

    x=-π/4

    general solution:

    x= 3pi/4+pi* n
     
    MathLover1, Mar 10, 2022
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  5. nycmathguy

    nycmathguy

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    You divided both sides by cos x. Could we also divide both sides by sin x, if needed?
     
    nycmathguy, Mar 10, 2022
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  6. nycmathguy

    MathLover1

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    yes, you can also divide both sides by sin x and got cot x
     
    MathLover1, Mar 10, 2022
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  7. nycmathguy

    nycmathguy

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    Thank you.
     
    nycmathguy, Mar 11, 2022
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