Calculate (7 + √3)(7 - √3)
(7 + √3)(7 - √3) = 72 + 7√3 - 7√3 - (√3)2 = 49 - 3 = 46Alternatively you can go straight to identifying that this is the difference between two squares, using the fact that (a + b)(a - b) = a2 - b2
IB
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