This 45-minute test has 9 questions worth 20 points. Calculators are not needed. Show your work for every question, give exact answers, and include units where a question has a context.
- Grade: AP Calculus AB
- Chapter: Definition of the Derivative and Basic Rules
- Common Core: AP Calculus AB Unit 2
- Time: 45 minutes
- Total: 20 points (Question 1: 2 pts; Question 2: 3 pts; Question 3: 2 pts; Question 4: 2 pts; Question 5: 3 pts; Question 6: 2 pts; Question 7: 2 pts; Question 8: 2 pts; Question 9: 2 pts)
Question 1: Limit definition (2 points)
Let \(f(x)=x^{2}-3x\). Use the limit definition of the derivative to find \(f^{\prime}(x)\).
Question 2: Basic rules (3 points)
Find the derivative of each function.
- \(f(x)=5x^{4}-2\sqrt{x}+7\) (1 point)
- \(g(x)=3e^{x}-4\sin x+2\ln x\) (1 point)
- \(h(x)=\frac{6}{x^{2}}+3\cos x\) (1 point)
Question 3: Product rule (2 points)
Let \(f(x)=x^{3}e^{x}\). Find \(f^{\prime}(x)\) and evaluate \(f^{\prime}(1)\).
Question 4: Quotient rule (2 points)
Let \(g(x)=\frac{2x+1}{x^{2}+1}\). Find \(g^{\prime}(x)\) and evaluate \(g^{\prime}(0)\).
Question 5: Tangent lines to a cubic (3 points)
The graph of \(f(x)=x^{3}-3x\) is shown.
- Write an equation of the tangent line at \(x=2\). (1 point)
- Find every \(x\) where the tangent line is horizontal. (1 point)
- Find every \(x\) where the tangent line is parallel to \(y=6x\). (1 point)
Question 6: Differentiable piecewise function (2 points)
Let \(f(x)=x^{2}+1\) when \(x\le 2\) and \(f(x)=ax+b\) when \(x > 2\). Find \(a\) and \(b\) so that \(f\) is differentiable at \(x=2\).
Question 7: Estimating rates from data (2 points)
The temperature \(T\) in \(^{\circ}\)F of a cup of coffee is measured \(t\) minutes after it is poured.
- Find the average rate of change of \(T\) on \([0,4]\). Include units. (1 point)
- Estimate \(T^{\prime}(6)\) using the points at \(t=4\) and \(t=8\), and explain what it means. (1 point)
Question 8: Derivative with tangent (2 points)
Let \(f(x)=x\tan x\). Find \(f^{\prime}(x)\) and evaluate \(f^{\prime}(\frac{\pi}{4})\).
Question 9: Motion along a line (2 points)
A particle moves along a line with position \(s(t)=t^{3}-6t^{2}+9t\) feet, \(t\ge 0\) seconds.
- Find the velocity \(v(t)=s^{\prime}(t)\). (1 point)
- Find every time the particle is at rest, and the position at each. (1 point)
See every chapter on the AP Calculus AB math page.


