# C4 – Exam Tip #1

### Differentiating

As part of the C4 content, you must know how to differentiate where is a constant.

The trick to finding when is first taking the natural logarithm of both sides of this equation:

Then use the laws of logarithms to bring the outside:

We can then differentiate both sides of this equation (this means differentiating the left hand side implicitly):

Note that is a constant and so

Finally, multiply both sides of the equation by …

…and remember that …

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