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A level Maths, C1 Questions (NEED HELP - I'M REALLY STRUGGLING WITH THESE QUESTIONS) watch

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    I need help with Question 2 especially and if someone could also guide me the right way about doing question 3, that would help.

    I've done Question 2a and got A = (2,0) (If someone could check that would be helpful!!!)

    With Question 2b, I tried to make 3y = 2x -12 into y^2 = 4/9x^2 + 16. Is that right? From there I tried factorising but I'm struggling to do it, please help! Thanks!


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    (Original post by AyyJeh)
    I need help with Question 2 especially and if someone could also guide me the right way about doing question 3, that would help.

    I've done Question 2a and got A = (2,0) (If someone could check that would be helpful!!!)

    With Question 2b, I tried to make 3y = 2x -12 into y^2 = 4/9x^2 + 16. Is that right? From there I tried factorising but I'm struggling to do it, please help! Thanks!

    Your a) is correct.

    For b), it's easier to substitute for something that isn't going to be squared. i.e.

    2x = 12 + 3y
    y^2 = 4x - 4

    Try substituting for x in the second equation. Post your working if you get stuck.
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    Ahhh I see, I will try this!
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    How do i do Question 2c?
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    (Original post by AyyJeh)
    How do i do Question 2c?
    Do you have any ideas? As soon as you see 'right-angle' in a C1 coordinate geometry problem, what should you be thinking about?

    Post your thoughts.
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    I'm thinking perpendicular lines when they intersect but I dunno how to do that if one line is a curve?
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    (Original post by AyyJeh)
    I'm thinking perpendicular lines when they intersect but I dunno how to do that if one line is a curve?
    The angle PAQ is made up of three points, P, A and Q. Ignore the curve - this question is about the angle formed by straight lines connecting these points.

    If you know the coordinates of these points then you can work out the gradients of the lines.

    Please quote me if you're asking/answering my question.
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    (Original post by notnek)
    The angle PAQ is made up of three points, P, A and Q. Ignore the curve - this question is about the angle formed by straight lines connecting these points.

    If you know the coordinates of these points then you can work out the gradients of the lines.

    Please quote me if you're asking/answering my question.
    I have the gradients:
    A and P = 2
    A and Q = 1/2
    Q and P = 2/3

    What do I do with these gradients? Do I use Pythagoras?
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    (Original post by AyyJeh)
    I have the gradients:
    A and P = 2
    A and Q = 1/2
    Q and P = 2/3

    What do I do with these gradients? Do I use Pythagoras?
    Your gradient for AP is incorrect. You should be able to see from the diagram that it has a negative gradient.

    Then what you you know about the gradients of perpendicular lines?
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    (Original post by notnek)
    Your gradient for AP is incorrect. You should be able to see from the diagram that it has a negative gradient.

    Then what you you know about the gradients of perpendicular lines?
    Ahh yeah, it's -2 my bad.

    Perpendicular is the negative reciprocal but how does that determine an angle? o_O
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    (Original post by AyyJeh)
    I'm thinking perpendicular lines when they intersect but I dunno how to do that if one line is a curve?
    (Original post by AyyJeh)
    How do i do Question 2c?
    TIP: Draw lines referenced in a question that aren't on the diagram provided. Mark in angles and lengths you know as well.
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    (Original post by AyyJeh)
    Ahh yeah, it's -2 my bad.

    Perpendicular is the negative reciprocal but how does that determine an angle? o_O
    Showing that the lines AP and AQ are perpendicular proves that angle PAQ is a right-angle.

    Draw the three points and check yourself.
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    Yeah, I just saw haha before you typed this! Thanks man! I really do appreciate your help!
 
 
 
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