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# OCR A2 maths problem watch

1. ABC is a right angled triangle as shown in the diagram. A rectangle AXYZ is drawn around the triangle, with the angle XAB = theta

By expressing the perimieter of the rectangle in the form R cos (theta - alpha), find:

a) the maximum perimieter of the rectangle as theta varies

b) the corresponding value of theta, giving your answer to the nearest 0.1 of a degree.

The picture I've attached is just a quick one I've drawn of the image I have on the pice of paper. The sides of the triangle I've been given are 2 and 1 as I've tried to show on my drawing.

How do I go about starting this? I'm literally blank.
2. What's |AX|? |XB|?

If you're stuck on something like this, just use trig/angle rules/pythagoras to work out as many lengths/angles as you can, and see if it gets you anywhere.
3. (Original post by Daniel Freedman)
What's |AX|? |XB|?

If you're stuck on something like this, just use trig/angle rules/pythagoras to work out as many lengths/angles as you can, and see if it gets you anywhere.

We're not given AX or XB, I've put everything we have on that diagram.

I'll have a quick look through my notes and revision book and see if I can find anything that looks like this tomorrow. I'll see if anyone else has done it as well.
4. (Original post by TheBlueNowhere)
We're not given AX or XB, I've put everything we have on that diagram.

I'll have a quick look through my notes and revision book and see if I can find anything that looks like this tomorrow. I'll see if anyone else has done it as well.
I meant "from the information given, what is |AX|"? There's enough information to find it in terms of theta, which is what you want.

EDIT: Changed '|AB|' to '|AX|'
5. theta=0 perimiter=6?

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