thanks loads, i'll try it out :)

"MrShorty" wrote:


I don't think Excel knows how to do this as a built in thing. Extract
the coefficients of the trendline to a worksheet (using a worksheet
function such as LOGEST or a utility that will extract trendline
coefficients to a worksheet). Then you can use the coefficients and
your knowledge of calculus to determine a formula for the slope of the
function at any point. Then use that formula to put together a series
of data points that you can plot as the tangent of the curve.


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MrShorty
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