Review question

# If $a\mathbf{i}+b\mathbf{j}+c\mathbf{k}$ is perpendicular to these vectors, what is $a:b:c$? Add to your resource collection Remove from your resource collection Add notes to this resource View your notes for this resource

Ref: R6493

## Question

Given that the vector $a\mathbf{i}+b\mathbf{j}+c\mathbf{k}$ is perpendicular to each of the vectors $5\mathbf{i}+3\mathbf{j}-4\mathbf{k}$ and $2\mathbf{i}-\mathbf{j}-6\mathbf{k}$, find the ratios $a:b:c$. Hence find a unit vector which is perpendicular to each of the vectors $5\mathbf{i}+3\mathbf{j}-4\mathbf{k}$ and $2\mathbf{i}-\mathbf{j}-6\mathbf{k}$.