A reader of our Mathtuition88.com blog asked the following Maths question:

**Given that and , where , express in terms of .**

This is a rather challenging question, since there are many options to start. Which formula(s) should we use? Factor formula? R-formula? Give it a try first if you want to have a challenge.

**Solution:**

It turns out we can write:

Then, use

Expanding,

Rearranging,

Since , we have .

Thus, .

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