The Angle Between the Vectors $5 \vec{i}-5 \vec{j}+\vec{k}$ And $4 \vec{i}+4 \vec{j}-\vec{k}$

Short Answer

The angle between the vectors $5 \vec{i}-5 \vec{j}+\vec{k}$ and $4 \vec{i}+4 \vec{j}-\vec{k}$ is---------. Round to the nearest whole number.