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## AP®︎/College Calculus BC

### Course: AP®︎/College Calculus BC>Unit 3

Lesson 6: Selecting procedures for calculating derivatives: strategy

# Differentiating functions: Find the error

Analyzing the work of students differentiating various functions to see if they made a mistake, and if so, what mistake.

## Want to join the conversation?

• Actually, i have a question, which KA perhaps can answer based on their interactions with the AP board: in that final (and clever) practice question, the answer was correct, but an algebraic step simplifying the approach was missed. Would the test scorers deduct points for that?

I guess that's a more general question: is it possible to stumble to the correct answer but, in showing work that failed to answer the question properly, have points deducted?
• I don't think so. Using the quotient rule was legit, but it's just that he could have gotten the same answer a lot faster if he simplified it the way Sal did. AP exams have a limited amount of time for you to answer all of the questions anyways, so it's better to not spend extra time on a question when it is unnecessary.
Just to answer your question more clearly; no, I don't think that points will be deducted if you fail to simplify your work but still get the right answer. But other than that, I guess it really depends on the situation. For example, if your work isn't clear or incomplete where they require you to show your work, but you still get the answer right, of course you should expect that a few points will be deducted. However, if it's multiple choice, you might get away with not showing your work. Don't quote me on that though, I might be wrong.
However, in general, it is good practice to show your work properly.