#### Stratosphere

1. The problem statement, all variables and given/known data

(square root of 3 + square root of 5)(square root of 3-square root of6)

2. Relevant equations

3. The attempt at a solution
Im confused on what to multiply what with.

#### The Bob

How would you multiply (x + y)(x - z) out?

The Bob

#### boaz

I don't know but that's what I've gotten :
$$(\sqrt{3}+\sqrt{5})(\sqrt{3}-\sqrt{6})=\sqrt{3}(\sqrt{3}-\sqrt{6})+\sqrt{5}(\sqrt{3}-\sqrt{6})=\\ \sqrt{3}\cdot\sqrt{3}-\sqrt{3}\cdot\sqrt{6}+\sqrt{5}\cdot\sqrt{3}-\sqrt{5}\cdot\sqrt{6}=\\ =-2.846882916$$

#### The Bob

Well that is a way to do it but you've not produced an 'accurate' answer by using surds. As this has been posted, Stratosphere what would you have done?

The Bob

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