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    x= sint + t, y= sint,

    a) find dy/dx in terms of t.b) Find, in exact form, the coordinates of the point where thetangent to the curve is parallel to the x-axisc) Show thatthe region bounded by the curve and the x-axis has area 2.

    I have done part a) and got the answer of cost/(1+cost) which I know is correct. I don't know how you do part b) and c) as there are no co-ordinates give. The curves touches the x-axis at 0 and another unlabelled point.
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    Improvement, please edit your OP
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    (Original post by Kvothe the arcane)
    Improvement, please edit your OP
    Just done it.
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    (Original post by Improvement)
    x= sint + t, y= sint,

    a) find dy/dx in terms of t.[/color][/color][/color][/color][/color]

    I have done part a) and got the answer of cost/(1+cost) which I know is correct. I don't know how you do part b) and c) as there are no co-ordinates give. The curves touches the x-axis at 0 and another unlabelled point.
    The tangent to the curve is parallel to the x axis when there is no gain in y, ie when dy/dx=0.
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    (Original post by Kvothe the arcane)
    The tangent to the curve is parallel to the x axis when there is no gain in y, ie when dy/dx=0.
    so it will be the TP co-ordinate of the curve? so I would make cos(t)/1+cost = 0?
    so cos(t) =0?
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    Got the answer to b) only need to do c now
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    (Original post by Improvement)
    so it will be the TP co-ordinate of the curve? so I would make cos(t)/1+cost = 0?
    so cos(t) =0?
    Indeed
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    (Original post by Improvement)
    Got the answer to b) only need to do c now
    Was there an image of the graph or a range?
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    (Original post by Kvothe the arcane)
    Was there an image of the graph or a range?
    It is in the positive quadrant of the graph and comes from the origin to an unmarked point of the x-axis where it ends.
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    (Original post by Improvement)
    It is in the positive quadrant of the graph and comes from the origin to an unmarked point of the x-axis where it ends.
    Any chance you can upload an image?
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    (Original post by Kvothe the arcane)
    Any chance you can upload an image?


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    So the limits are 0 and pi (I might be wrong).

    \displaystyle A= \int^{\alpha}_{\beta}y \ \dfrac{dx}{dt} \  dt
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    plain parametric integration
    limits are correct
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    (Original post by Kvothe the arcane)
    So the limits are 0 and pi (I might be wrong).

    \displaystyle A= \int^{\alpha}_{\beta}y \ \dfrac{dx}{dt} \  dt


    I have y obviously as sint and dx/dt = 1+cost so before integrating should I multiple the brackets? or just keep them as they are?
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    (Original post by Improvement)


    I have y obviously as sint and dx/dt = 1+cost so before integrating should I multiple the brackets? or just keep them as they are?
    Well you do what you think you need to do to integrate.

    Sent from my SM-G925F using Tapatalk
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    (Original post by Kvothe the arcane)
    Well you do what you think you need to do to integrate.

    Sent from my SM-G925F using Tapatalk
    I got the answer thanks guys!
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    No worries Improvement, I'm glad we were able to help.
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    (Original post by Kvothe the arcane)
    No worries Improvement, I'm glad we were able to help.
    you called my Lord?
 
 
 
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