What is the answer to (√2 - √3) ²?

A big part of math is pattern recognition. A lot of homework is just fighting with stuff so you will remember the pattern when you see it again. The most common pattern is (x + a) * (x + b) = x^2 + (a + b)x + ab and the special case (x + a) * (x - a) = x^2 - a^2. When you spot the pattern you can just write the answer from memory.

(√2 - √3) ²

√2 squared = 2
√2 x -√3 = -√6
-√3 squared = 3
-√3 x √2 = -√6
------------------- ADD
5 - 2√6

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