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    I've done part a) and part b) but have no idea how to work out part c. I've attached the question + worked solution as an image. I know the angle APB is a right angle, so I've been trying to work out the lengths AP and PB, so I could then use .5(AP)(PB), but I can't do that and the solution approaches a different, confusing method.
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    On the sample solution it looks like they've split the triangle into 2 by using the line y = 3\sinh(t) and then summed out the areas of them separately.

    Let the point on the y axis where x = 0 be D. This would allow you to use Area = \frac{1}{2}|AD||PD| + \frac{1}{2}|BD||PD|

    =\frac{1}{2}|PD| . (|AD| + |BD|)

    Does that help?
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    Ahh perfect, thanks. I was thinking earlier, why am I not using the distance between two points formula to work out the base and height? I.e \sqrt{(x_1-x_2)^2+(y_1-y_2)^2}
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    (Original post by ViralRiver)
    Ahh perfect, thanks. I was thinking earlier, why am I not using the distance between two points formula to work out the base and height? I.e \sqrt{(x_1-x_2)^2+(y_1-y_2)^2}
    Yeah it gets a bit messy that way!
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    Will it work, however? I'm now confused why both methods would work, since they're completely different xD .
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    (Original post by ViralRiver)
    Will it work, however? I'm now confused why both methods would work, since they're completely different xD .
    It would work, there's no reason why it wouldn't, but it's much more work and unfortunately time can be quite tight in FP3 if you choose the wrong methods!
 
 
 
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