- #1

- 363

- 79

- Homework Statement
- ##(\textbf{r}\times \dot{\textbf{r}})\times \textbf{r}=\dot{\textbf{r}}(\textbf{r}\cdot \textbf{r})-\textbf{r}(\textbf{r}\cdot\dot{\textbf{r}})##

Where ##\textbf{r}## is a vector

- Relevant Equations
- Vector cross and dot product

Hi guys,

I am losing my mind over this passage...

I cannot understand how to get from the first expression with the cross products to the second ##\dot{\textbf{r}}(\textbf{r}\cdot \textbf{r})-\textbf{r}(\textbf{r}\cdot\dot{\textbf{r}})##

I am losing my mind over this passage...

I cannot understand how to get from the first expression with the cross products to the second ##\dot{\textbf{r}}(\textbf{r}\cdot \textbf{r})-\textbf{r}(\textbf{r}\cdot\dot{\textbf{r}})##