Question

Calculati:
a) radical din 20+radical din 5
b) 7radical5-radical din 45
c) (2radical5-1)ori(radical 5+2)

Answer 1

√20=2√5=>√20+√5=3√5
√45=3√5=>7√5+√45=10√5
(2√5-1)(√5+2)=2*5+4√5-√5-2=8+3√5