conics help (1 Viewer)

zeebobDD

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okay for part iii this is what i did

I subbed in both the ordinates of Q and R into the eqt of the tangent

and after some algebraic work i got an expression of cos(q-p)=1/2, and cos(r-p)=1/2

then cos-1 both sides and get q-p=60, r-p=60

but adding the two equations has -2p in it:/ if it was -2p i could claim that q and p both differ by 2pi/3

so what did i do wrong?
 

Carrotsticks

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You didn't do anything wrong.

You simply forgot that:



So your cos(r - p) = cos (p - r) = 0.5

So we have:

 

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