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Tips for drawing graphs of form y^2=... watch

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    I'm having trouble drawing the graphs of equations in the form y^2=...

    For example, I can easily draw y=|x²-9|-7 and I can easily transorm this to y²=|x²-9|-7 for all the obvious points, but its in between these points I can't really get a feel for the shape of the graph.

    Anyone have any tips?

    (I would attach an image but it's too big)
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    its just [|x^2 - 9| - 7] times itself

    you need to remember that when a number is squared, it becomes bigger by a factor of itself, so when the number is less than one it will be smaller, when its considerably close to 0 it will be practically zero, and when tis considerably greater than 1, it will get huge.

    practice drawing sin^2 x, cos^2 x, and other similar things. tan^2 x, (e^x)^2, and you should get the hang of it.. also remember for real functions the curve should be above the x-axis!

    Im not sure there's an easier way than that.
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    The function is y²=|x²-9|-7 so it's y=(|x²-9|-7 )0.5

    not y=(|x²-9|-7)2
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    (Original post by mik1w)
    also remember for real functions the curve should be above the x-axis!
    The standard hyperbola y^{2}=4ax has a curvce above and below the x axis since y = \pm\sqrt{4ax}
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    argh. thanks for correcting me, I dont know what Im typing half the time. I think some content is right but 1. I completely misread the question, 2. I misanswered the misread question.

    sorry .. my bad. more often than not two wrongs don't make a right. (double negatives aren't not cool)
 
 
 
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