AP Calculus Free-Response Questions

Use the. definition of the derivative to justify your answer. c. Let k = 4. Determine whether f is differentiable at x = 4. Justify your answer. 90. A particle moves along the x-axis so that at time t its position is given by . x(t) = sin ( t2) for -1 < t < 1. a. Find the velocity at time t. ................
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