Trivial Question on Gamma Distribution Function

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If a random variable X follows Gamma Distribution Function with parameters K and thita, what does (X+k) follow? if K is a constant.
I think, since adding the constant is just like shifting the origin, the nature of the curve remain unchanged. But what about its parameter?
Thanks.
 
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Let X be the standard gamma distribution with parameter [itex]\alpha[/itex]. Then this has pdf

[tex]p_X(x)=\frac{1}{\Gamma (\alpha)}x^{\alpha-1} e^{-x}[/tex]

for x>0. Then we define the generalized gamma distribution as [itex]Y=a+\lambda X[/itex]. This has pdf

[tex]P_Y(x)=\frac{1}{\Gamma(\alpha)\lambda^\alpha}(x-a)^{\alpha-1}e^{-(x-a)/\lambda}[/tex]

if x>a. This is the [itex]\Gamma(\alpha,a,\lambda)[/itex]-distribution. The standard gamma is [itex]\Gamma(\alpha,0,1)[/itex]. So to answer your question:

if [itex]Y\sim \Gamma(\alpha,a,\lambda)[/itex], then [itex]Y+k\sim \Gamma(\alpha,a+k,\lambda)[/itex].
 
Thank you for your kind help.