So I have a consumer with a utility function of the Cobb-Douglas form $v(x_1,x_2)=x^{\frac{1}{2}}_1x^{\frac{1}{2}}_2$.
From that I constructed the demand function for good 1 and good 2:
$x_1=\frac{1}{2} \cdot \frac{m}{p_1}$
$x_2=\frac{1}{2} \cdot \frac{m}{p_2}$
From here, I am to determine whether good 1 and good 2 are substitutes or complements. I was told by my teacher to take the derivative with respect to $m, p_1$ and $p_2$, however I can't get a sensible result. As far as I've come to understand from my book, I need to find $\frac{dx_1}{dp_2}$, the change in the demand for good 1 as the price of good 2 changes. Substituting m back to $p_1x_1+p_2x_2$ becomes messy as well. I understand the problem theoretically, but I simply can't figure out how to properly argue using math, rather than logic.
I hope someone is willing to help
