Parametric equations and finding tangents from circles

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SUMMARY

The discussion focuses on finding the tangent line to a circle defined by the parametric equations x=1+2cos(θ) and y=3+2sin(θ). The derivative dy/dx is given as -1/tan(θ), which is used to determine the slope of the tangent line. The correct tangent equation at a point defined by the parameter θ is y - (3 + 2sin(θ)) = -cot(θ)(x - (1 + 2cos(θ))). The participants confirm the validity of this equation, emphasizing the importance of correctly applying the parametric equations and derivatives in the solution process.

PREREQUISITES
  • Understanding of parametric equations
  • Knowledge of derivatives and slopes of curves
  • Familiarity with trigonometric identities, specifically cotangent
  • Ability to manipulate algebraic equations
NEXT STEPS
  • Study the application of parametric equations in calculus
  • Learn about the derivation of tangent lines in polar coordinates
  • Explore trigonometric identities and their applications in calculus
  • Practice solving problems involving derivatives of parametric functions
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Students studying calculus, particularly those focusing on parametric equations and tangent line calculations, as well as educators seeking to enhance their teaching methods in these topics.

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Homework Statement


A circle has the parametric equations:
x=1+2cos\theta
y=3+2sin\theta

dy/dx= -1/tan\theta

Find the tangent equation at the point with parameter \theta

Homework Equations


y-y1=m(x-x1)


The Attempt at a Solution


I've tried putting dy/dx in as the gradient and then x1 and y1 as the parametric equations but i seem to come up with some really long equation that I am sure isn't right.

Any help at all would be greatly appreciated. Many thanks.
 
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You mean you don't think this is right?:

y-3-2sin\theta=-cot\theta(x-1-2cos\theta)

Because it is :-p
 

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