Hitunglah besarnya vektor C=2i-6j+8k + vektor 5i-3j-1k

C = (2+5)i – (6+3)j + (8-1)k
= 7i – 9j + 7k
|C| = √7²+(-9)²+7²
= √2(49)+81
= √98+81
= √279
= 17 satuan