Before Calculus: 10 Algebra Skills You Should Know
Review fractions, factoring and exponents when algebra is interrupting the calculus.
Get one-to-one help with limits, derivatives and optimization for John Abbott 201-SH2-AB. Work through a short business example below, or bring a question to a tutor, even if you have not started it.
John Abbott’s Calculus 1 for Social Science connects functions, limits and derivatives with curve sketching, optimization and business applications. You also work with exponential, logarithmic and trigonometric functions. Start with the calculation or interpretation that is slowing you down.
Review expanding brackets, function notation and reading an interval. In the example, you will turn a price and a cost into a profit function, differentiate a quadratic, and compare the permitted quantities.
In this simplified sales model, let be the number of items sold, treated as a continuous variable on . All items sell at the price dollars per item. The total cost is dollars. The fixed cost of 100 dollars applies even when no items are sold. Find the quantity that gives the largest profit, and state the corresponding price and profit.
First multiply the price per item by the quantity to get total revenue. Subtract the total cost, including the fixed cost. A zero derivative gives a candidate; check whether it is allowed and whether it really gives the largest profit.
Let be total revenue and be total profit, both in dollars. Revenue is price times quantity, and profit is revenue minus cost:
The derivative is the instantaneous rate of change of profit with respect to quantity, measured in dollars per item. It is zero at , positive for , and negative for . Profit therefore increases up to 40 items and decreases afterward.
The function is continuous on the closed interval . Check the interior candidate and the endpoints: The largest profit is 700 dollars at 40 items. This quantity is also a whole number, so it is feasible if items must be sold individually.
At , the price is dollars per item. Revenue is dollars and cost is dollars. Their difference is the profit: dollars.
The answer is a quantity of 40 items, a price of 30 dollars per item, and a profit of 700 dollars. The derivative’s value of zero is a rate, not the maximum profit.
Use the same price and cost model, but the seller can now sell at most 30 items. (1) Write the new interval for . (2) Find the quantity, price and largest profit on that interval. (3) Keeping this 30-item limit, suppose the fixed cost rises from 100 to 160 dollars. Does the best quantity change? What is the new maximum profit?
The formula has not changed in part (2), but the allowed interval has. For part (3), write the new profit as the old profit minus a constant.
The new interval is . The original candidate is outside it and cannot be chosen.
For , , so profit increases throughout the permitted interval. The maximum is at the endpoint .
The price is dollars per item. Revenue is dollars, cost is dollars, and profit is dollars. This is greater than . An endpoint maximum does not require a zero derivative.
Call the new profit . Then , so . Every profit value falls by the same 60 dollars; the maximizing quantity stays at 30 items and the price stays at 35 dollars per item. The new maximum profit is dollars.
If building the function was difficult, write the units beside price, revenue and cost. If the derivative was right but the conclusion was unclear, explain the sign change and check the endpoints before trying the self-check.
Bring a question, even if you do not know how to start. For a limit, your tutor can check the domain and the algebra before you substitute. For a derivative, they can help you choose the rule, keep every factor and check the result.
For a business application, your tutor can help you define the quantity and its units, build revenue or profit from the wording, and justify an optimum using the derivative and the domain. You can then try a changed version yourself and explain what stays the same.
Bring the topics your teacher has announced and a practice question, with any work you have started. Mix a limit, a derivative and an application from that scope. Explain the method before calculating, then redo a missed question without the solution. Follow your section’s instructions for permitted tools and assessment requirements.
Review fractions, factoring and exponents when algebra is interrupting the calculus.
Choose the product, quotient or chain rule, then check each factor.
Select questions on limits, continuity and derivative methods that match your current topics.
Yes. Send your course code, topic and preferred times. We confirm tutor availability, lesson details and price before payment.
Bring your current outline and a question you are allowed to share, if you have them. You can show any work you have started or ask your tutor to help you choose the first step.
Lessons are currently in English, online through Zoom or Google Meet.
Nablio provides independent tutoring and is not affiliated with or endorsed by John Abbott College.
Include 201-SH2-AB, the topic and a few times that work for you. You can add a practice question or any work you have started.
Ask about a lesson