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Tangent to a Curve

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A quadratic curve has equation $y = \\simplify{{a}x^2+{b}x+{c}}$.

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(a)  What is the equation the tangent to the curve at $x=\\var{x}$ ?

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       The equation of the tangent is required in  \\(y=mx+c\\)   form.

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       $y= $  [[0]]

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(b)  Find the coordinates of the point at which the tangent to the curve is horizontal.

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      \\((x,y) =\\)

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                          [[1]] 

\n

                   

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