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    9) a curve has equation y = x^2 - 3x + 1
    a) find the equation of the tangent to the curve at the point where x = 1
    b) find the equation of the normal to the curve at the point where x = 3

    I got a) as y=-x+2
    I got b) as y=-1/6x+3/2
    Do people agree?

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    (Original post by imaan2121)
    9) a curve has equation y = x^2 - 3x + 1
    a) find the equation of the tangent to the curve at the point where x = 1
    b) find the equation of the normal to the curve at the point where x = 3

    I got a) as y=-x+2
    I got b) as y=-1/6x+3/2
    Do people agree?
    Your gradient for the first one is correct but the rest is wrong I'm afraid. Can you please post all your working?
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    (Original post by imaan2121)
    9) a curve has equation y = x^2 - 3x + 1
    a) find the equation of the tangent to the curve at the point where x = 1
    b) find the equation of the normal to the curve at the point where x = 3

    I got a) as y=-x+2
    I got b) as y=-1/6x+3/2
    Do people agree?
    Can you please post future maths subject question in the maths forum please.
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    Could you please show your working?
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    (Original post by notnek)
    Your gradient for the first one is correct but the rest is wrong I'm afraid. Can you please post all your working?
    I think I did 2(3)-3 = 6 by accident haha, is this working below now right?

    for part b)
    dy/dx = 2x-3 when x=3 2(3)-3 = 3
    therefore the gradient of the normal is -1/3 x
    when x=3 y=1
    y-1=-1/3 (x-3)
    y= -1/3 x +2
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    (Original post by imaan2121)
    I think I did 2(3)-3 = 6 by accident haha, is this working below now right?

    for part b)
    dy/dx = 2x-3 when x=3 2(3)-3 = 3
    therefore the gradient of the normal is -1/3 x
    when x=3 y=1
    y-1=-1/3 (x-3)
    y= -1/3 x +2
    That's correct now.
 
 
 
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