Question

Dado vetor a = (1,2,1), determine k tal que kǁaǁ = 5.

Answer 1

Olá, Adondoka.

$k||a|| = 5\Rightarrow k\sqrt{1^2+2^2+1^2}=5\Rightarrow k\sqrt{6}=5\Rightarrow\\\\ k=\frac{5}{\sqrt6}\Rightarrow \boxed{k=\frac{5\sqrt6}{6}}$