Suppose our utility function is the usual CRRA utility with $\gamma=2$ so that: $$u(C) = \frac{C^{1-\gamma}}{1-\gamma} = -\frac{1}{C}$$
Now suppose there are 2 goods, A and B, available for consumption. The consumption of A and B are denoted $C_A, C_B$. How do I compute the final utility?
For example, if I just add the utility, then the summed utility will be less than consuming either one of the goods, because the utility function is negative. $$u(C_A) + u(C_B) = -\frac{1}{C_A} -\frac{1}{C_B} < u(C_A), u(C_B)$$
Suppose also that we want to make good B "more valuable". ie. 1 unit of good B should be worth more than 1 unity of good C. How would I reflect this in the utility function? A simple scaling with a value greater than 1 won't work, again because of the negative utility: $$u(C_A) + u(C_B) = -\frac{1}{C_A} -k \cdot\frac{1}{C_B}$$ where $k>1$
Thanks in advance.