Please help. The question is : Let the distribution function of X for x>0 be What is the density function of X for x>0? The answer is . some of the steps are Please can anyone show me step by step. I really don't understand. Thank you very much.
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Hey imp120. Have you tried differentiating each term in the series? Can you please show us your work?
Thank you very much.. I am a self learning , didn't go to school. Don't know what to do on this question.
Thank you so much for helping
Originally Posted by imp120 Since you are 'self-studding' it appears that your weakness is really in calculus. That will make much of this impossible for you to follow. $D_x(x^ke^{-x})=kx^{k-1}e^{-x}-x^ke^{-x}$ the $\large-$ comes from the derivative of $e^{-x}$.