If vectors \(\vec{a}\)= 3\(\hat{i}\) + 5 \(\hat{j}\)-7\(\hat{k}\) and \(\vec{b}\) = \(\hat{i}\)- 2 \(\hat{j}\) - 9\(\hat{k}\) then find the magnitude of vector (\(\vec{a}\) - \(\vec{b}\) )
Answer & explanation
Correct answer: option 3
We have vectors \(\vec{a}\)= 3\(\hat{i}\) + 5 \(\hat{j}\)-7\(\hat{k}\) and \(\vec{b}\) = \(\hat{i}\)- 2 \(\hat{j}\) - 9\(\hat{k}\)
then find the magnitude of vector ( \(\vec{a}\) - \(\vec{b}\)) = |{(3\(\hat{i}\) + 5 \(\hat{j}\)-7\(\hat{k}\)) -(\(\hat{i}\)- 2 \(\hat{j}\) - 9\(\hat{k}\))}|
= |{2\(\hat{i}\)+ 7\(\hat{j}\) +2\(\hat{k}\))}|
= √(2)2 +(7)2 +(2)2
= √57