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Exercise 2. Find the slope of the curve at the given point P as the limit of secant slopes Ay f(x th) - f(x) h as h approaches 0 (don't use derivatives here). Find an equation of the tan- gent line at P. er) f( ) = 12 - 3, P (2, 1); -b) g(x) = x2 - 4x, P(1, -3)