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The diagram shows a triangle ABC and the arc AB of a circle. What's this?

"The diagram shows a triangle ABC and the arc AB of a circle whose centre is C and whose radius is 24cm. The length of the side AB of the triangle is 32 cm. The size of the angle ACB is θ radians."

"Show that θ = 1.46 radians"

So i'm somehow supposed to *acquire 83 degrees from this and I cannot use both the sine and cosine rule. I've thought of *almost* everything with no success, how would you answer this?
Reply 1
Original post by OJ Emporium
"The diagram shows a triangle ABC and the arc AB of a circle whose centre is C and whose radius is 24cm. The length of the side AB of the triangle is 32 cm. The size of the angle ACB is θ radians."

"Show that θ = 1.46 radians"

So i'm somehow supposed to *acquire 83 degrees from this and I cannot use both the sine and cosine rule. I've thought of *almost* everything with no success, how would you answer this?


Using trig would be the obvious way, either split the isosceles triangle up into two identical right angled triangles, then use 2*asin (16/24) or use the cosine rule, but you said you're not allowed to use this. Why can't you use trig?
Original post by mqb2766
Using trig would be the obvious way, either split the isosceles triangle up into two identical right angled triangles, then use 2*asin (16/24) or use the cosine rule, but you said you're not allowed to use this. Why can't you use trig?

Oh not that I'm not allowed, apologies for phrasing it wrong but im not sure how
(edited 5 years ago)
Reply 3
Original post by OJ Emporium
Oh not that I'm not allowed, apologies for phrasing it wrong but im not sure how


Can you draw the diagram? If so, can you upload it?
Also, did you understand about splitting it up and using asin()?

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