# Limit question

## Answers and Replies

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andrewkirk
Homework Helper
Gold Member
It's almost right. The only problem is that $k$ may be negative. So multiplying the inequality by $k$ will change direction of the inequality, which will prevent reaching the conclusion.

Two ways to get around this are:

1. Do three separate cases, for k positive, negative and zero respectively; or
2. Multiply by $|k|$ instead.

2 is quicker, but you'll need to insert a few careful steps around where you multiply by $|k|$ to ensure that each one is valid.

Thank you very much!