Normal Distribution: Proving X Follows фX(x)=ф[(x-m)/σ]

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Show that if X is a normally distributed random variable with parameters mu and σ2, then then show that for each real number x we have:

фX(x)=ф[(x-m)/σ]
I have really hard time. Any possible hint is greatly appreciated.
 
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What is the definition of ф[(x-m)/σ], write out the left hand side and the right hand side.
 
I know that

Z= [X-μ]/σ or X=σ Z+μ

I also know that

f(x,μ,σ2)=1/ √(2πσ) e -(x-μ)2/(2σ2)=1/σ ф((x-μ)/σ)
 
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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