by tommywallach Wed Jan 21, 2015 2:59 pm
Hey Val,
It's a functions question, so whatever comes before the ampersand becomes the "v" in the new function. In this case, the v becomes (2v-1), so if you replace the v of (2v -1) with ANOTHER 2v-1), you end up with 2(2v-1) - 1
See how the thing in parentheses is just the new v?
-t