Bonjour j'aurai besoin d'un coup de pouce den proba/stat svp Voici l'exo
On considère une variable aléatoire discrète X défine par la loi de probabilité suivante :
xi , P(X=xi)
-5 , 1/4
-4 , a
1 , 1/2
2 , 1/8

1/Calculer a
2/Calculer l'espérance et la variance de X

C'est un QCM choix possible A.8.25 , B. 1/8,C.0, et D.-1

Pour 1/ je pense que la somme des P(X=xi) doit être égale à 1 donc réponse 1/8
Pour 2/ je pense qu'il faut d'abord dire qu'elle suit telle type de loi (normale ?) et après esperance = moyenne/médiane non ?

Merci beaucoup d'avance

The triangles in the diagram are congruent. if mzf = 40°, mza = 80°, and mzg = 60°, what is mzb?

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Have you ever been in the middle of telling a story and had to use hand gestures or even a drawing to make your point? in algebra, if we want to illustrate or visualize a key feature of a function, sometimes we have to write the function in a different form—such as a table, graph, or equation—to determine the specific key feature we’re looking for. think about interactions with others and situations you’ve come across in your own life. how have you had to adjust or change the way you represented something based on either the concept you were trying to describe or the person you were interacting with? explain how the complexity or layout of the concept required you to change your style or presentation, or how the person’s unique learning style affected the way you presented the information.