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A quadratic is and a graph of it is given. A tangent is also sketch. The equation of the tangent line is asked for.

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See Week 10 and 11 for background on differentiation. See Maths 1 for equations of a straight line.

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{plot(a,b,c,x, fx)}

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The curve with equation $y = \\simplify{{a}x^2+{b}x+{c}}$ is sketched above. The tangent to the curve at $x=\\var{x}$ has also been drawn. 

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What is the equation of the tangent line?

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$y=$ [[0]]

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