Question

a=radical125-radical5
b=radical (4radical5-8)^2
determinati media aritmetica a numerelor a si b

Answer 1

$a= \sqrt{125} - \sqrt{5} =5 \sqrt{5} - \sqrt{5} =4 \sqrt{5} \\ b= \sqrt{(4 \sqrt{5}-8)^2 } =|4 \sqrt{5} -8|=4 \sqrt{5} -8 \\ m_a= \frac{a+b}{2} = \frac{4 \sqrt{5}+4 \sqrt{5} -8 }{2} = \frac{8 \sqrt{5} -8}{2} = \frac{2(4 \sqrt{5} -4)}{2} =4 \sqrt{5} -4$