Answer:
4.85 units
Step-by-step explanation:
We can represent the situation as follows:
Then, we can use the cosine law to find the magnitude of A+B as follows
![A+B=\sqrt[]{A^2+B^2-2AB\cos \theta}](https://img.qammunity.org/2023/formulas/physics/college/b8ebgfrqh70krtzf2kt4wjr3aluaunag0j.png)
Where A and B are the magnitudes of vectors A and B, and θ is the angle between them.
So, replacing the values, we get:
![\begin{gathered} A+B=\sqrt[]{4^2+5.4^2-2(4)(5.4)\cos 60} \\ A+B=\sqrt[]{16+29.16-21.6} \\ A+B=\sqrt[]{23.56}=4.85 \end{gathered}](https://img.qammunity.org/2023/formulas/physics/college/dmth9yzdnxpoi3lzgiistkph7414nnnz0g.png)
Therefore, the magnitude of A+B is 4.85 units