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**williamb** Consider the function f(x) = 3x^(3)-5x^(2)-6

a) find [f(x+h) - f(x)]/h

(I found: 9x^2 + 9xh+3h^2-10x-5h, which is correct)

b) Find the derivative of f at x

(I found: 9x^2 - 10x, which is correct as well)

***c)What is the slope of the tangent line to the graph of f at the point (4,f(4))?

I don't know where to sub in these values, i tried substituting x=4 and y=4 into f(x) = 3x^(3)-5x^(2)-6 as well as 9x^2 + 9xh+3h^2-10x-5h to get the slope but in all honesty i don't have a clue

what is the "slope of tangent line" equation? i thought it was [f(x+h) - f(x)]/h as h approaches 0-- yes? no?

please help me out here,

thanks

Brittany