Trignometric identiy (LOADS o HELP ;D )

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SUMMARY

The discussion centers on solving the trigonometric identity equation involving sine and cosine functions: sin(pi + A) / cos(2pi + A) + sec(pi - A) / csc(2pi + A) = 0. Key identities utilized include sin(pi + A) = -sin(A) and cos(2pi + A) = cos(A). The periodic nature of trigonometric functions is emphasized, particularly that f(2pi + A) = f(A). The simplification of terms like sin(pi) and cos(2pi) to 0 and 1, respectively, is crucial for solving the equation.

PREREQUISITES
  • Understanding of trigonometric identities, specifically sin(x+y) and cos(x+y).
  • Familiarity with the properties of periodic functions in trigonometry.
  • Knowledge of reciprocal identities such as csc(x) = 1/sin(x) and sec(x) = 1/cos(x).
  • Ability to manipulate algebraic expressions involving trigonometric functions.
NEXT STEPS
  • Study the derivation and application of trigonometric identities in various contexts.
  • Learn about the periodic properties of trigonometric functions in depth.
  • Explore advanced trigonometric equations and their solutions.
  • Practice simplifying complex trigonometric expressions using identities.
USEFUL FOR

Students studying trigonometry, educators teaching trigonometric identities, and anyone looking to enhance their problem-solving skills in trigonometric equations.

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Homework Statement



sin(pi +A) sec(pi-A)
--------- + ---------- = 0
cos (2pi + A) csc(2pi-A)

Homework Equations


cscx=1/sinx
secx=1/cosx
sin(x+y)=sinxcosy+cosxsiny
sin(x-y)=sinxcosy-cosxsiny
cos(x+y)= cosxcosy-sinxsiny
cos(x-y)= cosxcosy+sinxsiny

The Attempt at a Solution


LS
sin pi cosA + cosA sin pi || 1/cos pi cos A + sin pi sin A
------------------------ + --------------------------
cos 2pi cosA + sin 2pi sinA || 1/sin pi cos A - cos pi sin A


the || is a seperator of the fractions

^
if it helps, i got this one to equal zero :)
 
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First off, use the identities that involve the sum of pi and an angle. E.g., sin(pi + A) = -sin(A) and cos(pi + A) = -cos(A). Also, cos(2pi + A) = cos(A) and so on.

Since all of the trig functions are periodic with period 2pi, f(2pi + A) = f(A), where f represents sine, cosine, tangent (yes I know that tangent's period is pi), and all the rest.

In the work you did, you have sin(pi) and cos(2pi) and all. Simplify those to 0 and 1, respectively.
 
Is this your equation?

[itex]\frac {\sin (\pi+A)}{\cos(2\pi+A} \ + \ \frac{\sec(\pi-A)}{\csc(2\pi+A)} \ = \ 0[/itex]
 

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