Update 3_vector_spaces.md

src/3_vector_spaces.md

@@ -188,7 +188,7 @@ Therefore, we see that the scalar product of vectors in Euclidean space can be e
 ## Problems
 
 **1)** [:grinning:] Find a unit vector parallel to the sum of $\vec{r}_1$ and $\vec{r}_2$, where we have defined
-$$\vec{r}_1=2\vec{i}+4\vec{j}-5\vec{k}$$ and $$\vec{r}_2=\vec{i}+2\vec{j}+3\vec{k}$$.
+$$\vec{r}_1=2\vec{i}+4\vec{j}-5\vec{k} \, , $$ and $$\vec{r}_2=\vec{i}+2\vec{j}+3\vec{k} \, .$$.
 
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@@ -207,8 +207,7 @@ Find the following quantities
 
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-**4)** [:grinning:] Find the vector product $\vec{b}X\vec{c}$ and the triple scalar product $\vec{a}\cdot(\vec{b}x\vec{c})$, where 
-
+**4)** [:grinning:] Find the vector product $\vec{b} \cross \vec{c}$ and the triple product $\vec{a}\cdot(\vec{b} \cross \vec{c})$, where 
 $$\vec{a}=\vec{i}+4\vec{j}+\vec{k}$$ and $$\vec{b}=-\vec{i}+2\cos{t}+2\vec{k}$$ and $$\vec{c}=2\vec{i}-\vec{k}$$
 
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