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Trigonometric Identities and equations

  • Thread starter wei1006
  • Start date
  • #1
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1) Problem statement:
Solve the trigonometric equation for the domain is. 0°<x<360°
5(sinx - cosx) = 4sinx - 3cosx

2) Relevent equations:
secx=1/cosx
cosec x=1/sinx
cot x= 1/tanx
tan x=sinx/cosx
cot x=cosx/sinx
sin^2 x + cos^2 x=1
1 + tan^2 x= sec^2 x
1+ cot^2 x = cosec^2 x

Template of answer:
New domain:
Basic angle=
Quadrants=
Solve for x
3)Attempt the question
5(sin x - cosx)=4sinx - 3cosx
5sinx-4sinx-5cosx+3cosx=0
sinx - 2 cos x=0
 

Answers and Replies

  • #2
Orodruin
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sinx - 2 cos x=0
Fine up to here, so what is the solution to this equation?
 
  • #3
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I am not sure how to continue...
 
  • #4
Orodruin
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How about trying to rewrite it by placing the 2 cos x on the other side and then dividing by something that makes it easier?
 
  • #5
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Thank you for your help, have solved it
 

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