" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2025 KUDO.TIPS - All rights reserved.
Verified answer
VEKTORAB = c
c= B - A
= (2,-1,1)
IcI = V6
AC = b
b = C - A
= (1,1,2)
IbI = V6
Maka
b.c = lbllclcosθ
cos θ = 1(2)+1(-1)+2(1) / (V6)^2
= 4-1 / 6
= 3/6 = 1/2
arc cos 1/2 = 60°