1) sin 60= √3/2
cos 60= 1/2
sin 30= 1/2
cos 30= √3/2
√3/2 + 1/2/√3/2 -1/2= √3/2 + 1/2 * 2/√3 -1/2=
= √3/2 + 1/√3 -1/2= rationalizam
=√3/2 +√3/3 -1/2 aducem la acelasi numitor
=(3√3+2√3-3)/6= (5√3-3)/6
2)x²-4x +4 +y²+6y+9 -3=-3
(x-2)²+(y+3)²-3+3=0
(x-2)² +(y+3)²=0
x-2=0 y+3=0
x=2 y= -3