Strip the Signs, Then Ask Twice

You'll learnto strip the signs off a series and ask about the sizes first, to read the label off a pair of answers rather than off a single test, to carry convergence upward from the sizes and never downward, and to check both conditions of the alternating series test before you use what it says.

This topic is not a new test but a name, and the name is settled by a series nobody gave you: strip every sign off the terms and ask about that one first. If it converges you are finished. If it does not, one question is left, and answering it by looking at the series you already have is the commonest error in the unit. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · ASK ABOUT THE SIZES FIRST · v2

Strip the signs, ask about that series first, and the label follows

Before you start

What you're looking at

Dots at the whole numbers along the bottom. Almost every one is a running total, so dots that flatten onto a lime rule mean the series settles there, and dots that keep climbing mean it never does.

The question

Pink is the series itself and teal is the same series with every sign stripped off. Which of the two decides what the series is called?

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