Tangent Line on a Parametric Curve

suchgreatheig
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Homework Statement


A curve is defined parametrically by x=sin3t, y=cos3t, 0≤ t ≤ 2pi. Find the equation of the line tangent to the curve at the point defined by t=2pi/9.


Homework Equations





The Attempt at a Solution


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suchgreatheig said:

The Attempt at a Solution


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Since you need to find the equation of a tangent, what do you need to find this equation?
 
I know that I need a derivative which I got as -3sinst/3cos3t, but I'm stuck from there.
 
suchgreatheig said:
I know that I need a derivative which I got as -3sinst/3cos3t, but I'm stuck from there.

so if dy/dx=-sin(3t)/cos(3t), what is the gradient when t=2π/9 ?
 
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