AE_L_ CD : => <) DAE =30 grade
DE=10/2 =5 cm
AE^2 =10^2-5^2 =100-25 =75
AE =5 rad 3 cm
SAU
sin 60 =AE/10
rad 3/2 =AE/10
AE =rad3*10/2 =5 rad 3 cm
