Gain some experience working with secant lines. This will help us on our journey to find a formal definition for the derivative.
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5032_Slope_of_a_line_secant_to_a_curve.html
5035_Secant_lines_with_simplification_arbitrary_difference.html
5033_Slope_of_secant_lines_arbitrary_difference.html
5037_Slope_of_secant_line_challenge.html
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