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Homework Help: Solving a trignometric equation.

  1. Mar 25, 2013 #1
    1. The problem statement, all variables and given/known data
    Hello, I'm having some trouble with this: 3cosX+4sinX=2.

    2. Relevant equations

    3. The attempt at a solution
    It's one of those problems where I've no idea of where to start. Could I possibly subtract 4sinX from both sides to get 3cosX=2-4sinX? And divide both sides by 3 to get cosX=(2-4sinX)/3? If this is right, it's from this point on that I'm confused. Thank you. The other problems were a bit simpler. 2 people, both Calculus tutors, couldn't help me on it.
  2. jcsd
  3. Mar 25, 2013 #2
    Try to convert it in a form cosXsinθ+sinXcosθ=k which you can then rewrite to the form sin(θ+X)=k.
  4. Mar 25, 2013 #3
    Oh, yep I see. Thank you. It's kind of late here, I'm going to bed, but I'll try it tomorrow morning. I remember my teacher showing us something like this.
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