How to Answer 'Hence' and 'Hence or Otherwise' Questions

“Hence” and “hence or otherwise” are among the most misread command words in 0606, and misreading them costs time and marks. Both signal the same thing: your previous answer is the key to this part. The difference is how strictly you’re required to use it.

”Hence” means: use what you just found

When a question says “hence”, it’s instructing you to use the immediately preceding result. The examiner has engineered the question so that your last answer unlocks this one, and a completely independent method may not earn the marks, even if it reaches the right answer. So the first move on seeing “hence” is to look back at what you just proved or calculated and ask how it feeds in.

This is common after a factor-theorem part (“hence solve the cubic”), or after a differentiation part (“hence find the coordinates of the stationary point”). The previous answer isn’t decoration, it’s the tool.

”Hence or otherwise” means: you may, but any correct method counts

“Hence or otherwise” is more generous: you’re free to use the previous result, or any other valid method, and full marks are available either way. But the word “hence” is still a strong hint. The previous part is almost always the intended, fastest route, so use it unless you have a clear reason not to. Students who ignore the hint and restart from scratch usually make more work for themselves and more chances to slip.

Why the previous part is your best friend

In both cases, treat the earlier answer as a gift. Examiners build multi-part questions as a ladder: each rung supports the next. A part you found hard becomes easier once you notice the previous answer was designed to help. When you see “hence”, your first thought should always be: what did I just get, and how does it plug in here?

The time-saving payoff

Reading these words correctly saves real time. Using the previous result is nearly always shorter than an independent method, and time saved on one question is time banked for a harder one, which matters when pacing the whole paper. Misreading “hence” and restarting is a classic way to run short on time.

A specialist trains this instinct, spotting when a “hence” is pointing back at the previous part, quickly. It’s part of the exam technique the trial class assesses. See also command words decoded and how to approach an unseen question.