Karan

How would I find the domain and range of a function f(g(x)) if I have the domain of both f(x) and g(x)? For a simple example, if I have f(x) = x + 2 where x>10 and g(x) = 2x - 1 where x≤20, what would I do to find the domain and range of f(g(x)) without actually graphing them out? Thanks!

So there's this big debate in math whether or not we should use tau or pi for all of our calculations. What do you think? What should we use?

Several years ago, I learned about this number, which can be multiplied by any regular polygon's perimeter squared to get the polygon's area. I learned this number as the Greek letter phi, which can be multiplied in the correct subscript to a figure's perimeter squared to get its area (for example, you would multiply phi with a subscript of 5 to the perimeter of a regular pentagon squared to get its area. I can't find a link anywhere talking about this concept or number or whatever it is, so could anyone please explain it to me or link me to an explanation? Thanks!