Question 1065509
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If (a - b)^2 = 5 and ab = 1, find the positive value of a + b.
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If (a-b)^2 = 2, then a^2 - 2ab + b^2 = 5.


Hensce,  a^2 + 2ab + b^2 = (a^2 - 2ab + b^2) + 4ab = 5 + 4 = 9.


In other words, (a+b)^2 = 9.


Then a + b = 3.


It is the same as the Fombitz' solution, but more straightforward.
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