Răspuns:
a = 13
Explicație pas cu pas:
a = √(√8-4)²+√(√18-6)²+5√(1-√8)² + √(√50-8)² =>
a = I√8-4I + I√18-6I + 5·I1-√8I + I√50-8I =>
a = I√8-√16I + I√18-√36I +5·I√1-√8I + I√50-√64I =>
a = 4-√8+6-√18+5(√8-1)+8-√50 =>
a = 4-2√2+6-3√2+10√2-5+8-5√2 =>
a = 4+6+8-5-2√2-3√2-5√2+10√2 =>
a = 13