Can someone help me with this circle geo Question (1 Viewer)

StudyMaster101

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Yeah i'm a bit lost.

Its from cambridge yr 11 3u, Exercise 14H Q18

I think you use A=1/2 (absinC)

Screenshot (2).png

Thanks.
 

Drongoski

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Yeah i'm a bit lost.

Its from cambridge yr 11 3u, Exercise 14H Q18

I think you use A=1/2 (absinC)

View attachment 34563

Thanks.
Since PSQ is right-angled at S, PS = d cos @

Using: Area of triangle A = "(1/2)absinC" = (1/2) dcos@ x dcos @ x sin @ = (1/2)d2cos2@sin @

dA/d@ = 0.5d2cos@(1-3sin2@) = 0 when A is maximum.

Solving: sin2@ = 1/3

Substitute this into A = 0.5d2(1 - sin2@)sin@
you get A-max = the reqd result.
 
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