Question

I need help with this practice problem solving My attempted answer is in the pic, though I am not sure if I am correct or not

Answer 1

To convert from polar coordinate to rectangular coordinate,

`\begin{gathered} (r,\theta)\to(r\cdot\cos \theta,r\cdot\sin \theta) \\ \\ \Rightarrow(3\sqrt[]{5},-(\pi)/(8))\to(3\sqrt[]{5}\cdot\cos (-(\pi)/(8)),3\sqrt[]{5}\cdot\sin (-(\pi)/(8))) \\ \\ \Rightarrow(3\sqrt[]{5}\cdot\cos (-(\pi)/(8)),3\sqrt[]{5}\cdot\sin (-(\pi)/(8)))=(6.20,-2.57) \end{gathered}`