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Homework Help: Component Identities

  1. Oct 4, 2005 #1
    Solve for x

    3sin(x+10)=4cos(x-10)

    I tried changinf everything into tan nothing out. I tried expaning the brackets and collecting like terms, that didnt work out either.
    Please help.
     
  2. jcsd
  3. Oct 4, 2005 #2

    Astronuc

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  4. Oct 4, 2005 #3
    Yeh, but I cant simplify anything to solve the problem
     
  5. Oct 4, 2005 #4

    Astronuc

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    Well expand the sin and cos and apply cos (-x) = cos x, and sin (-x) = -sin x.

    Then collect terms/coefficients of cos x and sin x.

    If one has a form A cos x = B sin x, the tan x = A/B and x = tan-1 (A/B). In this problem A and B have terms of sin 10 and cos 10.
     
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