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# C2 Trig, worrying q watch

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1. Need help yet again!

Question Seven parts a and b, dunno how to start. Maybe pythagorus? Dumbfounded.

2. (Original post by rye225)
Need help yet again!

Question Seven parts a and b, dunno how to start. Maybe pythagorus? Dumbfounded.

3. I just cannot read some of that question - You're causing more problems than you need to make.
4. The shaded region in the diagram shows a component for a machine, which is to be cut from a square piece of metal PQRS, of centre O and side 8cm. The outer edge of the component is the regular octagon ABCDEFGH, and the inner edge is the circle centre O and radius 3cm. Calculate:

a) The area of the component
b) The outer perimeter of the component

---

Not actually sure how to answer it, just thought I'd help y'all out.
5. a) Split the octagon into triangles.

OC=OF=OE and so on, and all of them equal 4. The angle in between the longest lengths = 360/8.

Work out the area of the octagon from that and then subtract the area of the circle.

b) Using the triangles again, because you already know the length of 2 sides and the angle in between them, you should be able to work out the length of the shortest side of the triangle, then multiply that by 4 to get the total perimeter.

Unless I totally missunderstood the question is very likely.

P.S. please preview next time. My nose was touching the computer screen when I was reading the question.
6. Yep, it's all triangles and circles.
7. thx man, and soz about the zoom lol

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