write the equation of the line tangent to the graph pf f(x) at x=1, f(x)=2x^2+9x

Graph Both equations on the same graph

In order to find the equation of this straight line you'll need to know at least one point the line passes through and its gradient. Let x=1, that's a convenient number. What will the value of y (or f(x) if you prefer) for this value of x? For the next stage you'll need to remember that a tangent has the same gradient as the curved line at the point of contact.
19 February 2012
To determine the gradient of the tangent you will need to be able to differentiate f(x). Contact me if you need any help with differentiation.
26 February 2012
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