Finding the domain of a composite function

lindseyam
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Homework Statement



I started out with f(x)=sinx and g(x)=1-√x. I found f(g(x)) which is sin(1-√x) and now my problem is how to find the domain. I've really been struggling with the domain part and just need this one done step by step so i have an idea of how to actually do it.

Homework Equations





The Attempt at a Solution

 
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start with finding the domain of g(x) and f(x)
 
lanedance said:
start with finding the domain of g(x) and f(x)

If I knew how to get the domain I would but I'm having trouble with the domain for both parts.
 
ok so what's your definition of domain?

Unless it is defined otherwise, I would informally interpret it as the region of input variable over which the function is valid

lets start with an easy but relevant example, what is the valid domain of [\itex]\mathbb{R} [/itex], for the function [\itex]h(x) = \sqrt{x}[/itex]
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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