Tolong ya 1-3 beserta caranya please dikumpul sebentarr Mohon bantuannya kakak kakak sekalian

jawab
1.
a = (3 , √3)
|a| = √(3²+ (√3)²) = √(9+3)= √12 = 2√3
tan a = √3/3 = tan 60
a = 60°

b= (-10, 6)
|b| = √ ((-10)² + 6²) = √136 = 3√14
tan b = 6/-10 = - 3/5 =  - tan 31
b = 180 - 31 = 149°

c =(4√3, -4)
|c| = √{(4√3)² +(-4)²} = √(48 +16) = 8
tan c = -4/4√3 = - 1/3 √3 = - tan 60
c = 360 - 60= 300

2) A = (4,7), B = (16,2)
AB = b - a = (16-4),(2-7) = (12, -5)
|AB| = √(12² +(-5)²)= √169 = 13
tan (AB) = - 5/12 = - tan 22,62
<AB = 360 - 22,62= 337,38

3) a(2,1, -2) , b (1,2,-2)
cos (ab) = { 2(1) + 2(-2)  -2(-2)} / (√2²+1²+(-2)² + 1²+2²+(-2)²)
cos (ab) = ( 2-4+4)/ (√(4+1+4+1+4+4)
cos (ab)= 2/√18 = 2 (3√2) / 18= 1/3 √2 = cos 62
<ab = 62