Question

one root of equation aX square - 3 x + 1 = 0 is 2+i find the value of a

Answer 1

$given \: \: one \: \: root = 2 + i \\ so \: \: other \: \: root = 2 - i \\ product \: \: of \: \: roots \: \: \\ \frac{1}{a} = (2 + i)(2 - i) = 4 + 1 = 5 \\ so \: \: a = \frac{1}{5}$