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    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.
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    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.
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    (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.
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    (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|'
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    theta=0 perimiter=6?
 
 
 
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