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    19 ii) We haven't been given any value for t, so I found t = 0, by setting sin2t = 0, since when x intercepts the axis y is 0. But this only gave me one of the the points on the graph.
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    (Original post by znx)
    19 ii) We haven't been given any value for t, so I found t = 0, by setting sin2t = 0, since when x intercepts the axis y is 0. But this only gave me one of the the points on the graph.
    Well there are multiple solutions to the equation \sin(2t) = 0 in the region 0 \leq t \leq \pi. You find them all the time in C2 and C3.
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    (Original post by RDKGames)
    Well there are multiple solutions to the equation \sin(2t) = 0 in the region 0 \leq t \leq \pi. You find them all the time in C2 and C3.
    thank you, forgot about the rest of the solutions
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    (Original post by RDKGames)
    Well there are multiple solutions to the equation \sin(2t) = 0 in the region 0 \leq t \leq \pi. You find them all the time in C2 and C3.
    For part iii) I've got it in the form Rcos(t-a), where R is √5 and a is 1.1
    For the coordinates of C, I got it as (1.1, √5) however the answer is (√5, 4/5) and im not sure why?
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    (Original post by znx)
    For part iii) I've got it in the form Rcos(t-a), where R is √5 and a is 1.1
    For the coordinates of C, I got it as (1.1, √5) however the answer is (√5, 4/5) and im not sure why?
    You found the max on the t-x graph, and not on the x-y graph.
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    (Original post by RDKGames)
    You found the max on the t-x graph, and not on the x-y graph.
    So the x should be √5, but why is y's coordinate found by sin(2a)? and not tan(a) or sin(a)?
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    (Original post by znx)
    So the x should be √5, but why is y's coordinate found by sin(2a)? and not tan(a) or sin(a)?
    Because the max x coordinate occurs when t=\alpha. Clearly the y coordinate for this is \sin(2t) = \sin(2\alpha).
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    (Original post by RDKGames)
    Because the max x coordinate occurs when t=\alpha. Clearly the y coordinate for this is \sin(2t) = \sin(2\alpha).
    Thank you
 
 
 
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