Question

F=i+2j+k,V=4i-j=7k then find F.V?​

Answer 1

Answer:

Explanation:

Given,

$F=\hat{i}+2\hat{j}+\hat{k}$

$V = 4\hat{i}-\hat{j}+7\hat{k}$

Solution :-

F.V :-

$F.V=(\hat{i}+2\hat{j}+\hat{k})(4\hat{i}-\hat{j}+7\hat{k})$

$=\hat{i}(4\hat{i})+2\hat{j}(-\hat{j})+\hat{k}(7\hat{k})$

= 4 - 2 + 7

= 4 + 7 - 2

= 11 - 2

= 9