Question

Explicati-mi si mie va rog cum se rezolva:
a=Ι5√3-6√5Ι
b=Ι5√3+6√5Ι
Rezolvati media geometrica dintre a si b.
Nu inteleg cum e cu modulul

Answer 1

$a=|5 \sqrt{3} -6 \sqrt{5} |=6 \sqrt{5} -5 \sqrt{3} \\ b=|5 \sqrt{3} +6 \sqrt{5} |=6 \sqrt{5} +5 \sqrt{3} \\ m_g= \sqrt{a \cdot b} = \sqrt{(6 \sqrt{5} -5 \sqrt{3} )(6 \sqrt{5} +5 \sqrt{3} )} = \sqrt{180-75} = \sqrt{105}$