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    (Original post by upthegunners)
    I drew the graph but I not sure what I should be looking for that indicates a change in direction...

    I guess it's because the negative time indicates the opposite direction and we only have 2 solutions, one positive and one negative?
    No you sound a bit muddled. The change in direction occurs when the velocity moves from negative to positive.
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    (Original post by Mr M)
    Yes if you just graph positive t. Alternatively you could integrate to find an expression for displacement and graph that.
    I graphed +t and it's is just a steep line..
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    (Original post by Mr M)
    No you sound a bit muddled. The change in direction occurs when the velocity moves from negative to positive.
    Meh.. yea I am confused :lol: (Is this point I would be kicked out of your class Mr M? haha, jokes )

    EDIT: In my GCSE class my Maths teacher called us "stupid" as we couldn't do something that her "1st years could do" :lol:
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    (Original post by upthegunners)
    I graphed +t and it's is just a steep line..
    Oh blimey! You misunderstood me.

    I want you to graph the quadratic v=3t^2+3t-18 where v is on the y axis and t is on the x axis and you only graph POSITIVE values on the horizontal t axis.

    How many times does the velocity change sign? This is the indicator of a change in direction.
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    (Original post by Mr M)
    Oh blimey! You misunderstood me.

    I want you to graph the quadratic v=3t^2+3t-18 where v is on the y axis and t is on the x axis and you only graph POSITIVE values on the horizontal t axis.

    How many times does the velocity change sign? This is the indicator of a change in direction.
    Do I just use any t values?
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    (Original post by upthegunners)
    Do I just use any t values?
    0 to 4 will do.
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    (Original post by upthegunners)
    Solve:Attachment 208995

    Okay so I draw my quadrant diagram like this:

    Attachment 208996

    thanks
    If you're a visual person, draw the graph of y=cos2x, and then draw the line y=0.5 and see where it touches (might help you a little)?
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    (Original post by Mr M)
    Oh blimey! You misunderstood me.

    I want you to graph the quadratic v=3t^2+3t-18 where v is on the y axis and t is on the x axis and you only graph POSITIVE values on the horizontal t axis.

    How many times does the velocity change sign? This is the indicator of a change in direction.
    Hi Mr M

    In the trig question I first posted about (from an exam paper) the question before it asked us to draw the graph of

    Does this bare any significance to the next question? Have they included that question to help us with the next one?

    Thanks
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    (Original post by upthegunners)
    Hi Mr M

    In the trig question I first posted about (from an exam paper) the question before it asked us to draw the graph of

    Does this bare any significance to the next question? Have they included that question to help us with the next one?

    Thanks
    Yes that makes the next bit a little easier. You will see that there are two periods of the curve and that there are 4 solutions and their approximate values.
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    (Original post by Mr M)
    Yes that makes the next bit a little easier. You will see that there are two periods of the curve and that there are 4 solutions and their approximate values.
    thank you
 
 
 
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