f[x_] := x^2

Integrate[f[x],x]

D[f[x],x]

Integrate[f]

Plot[f[x],{x,0,2}]

?Exp

?PoissonDistribution

g[x_]:=PoissonDistribution[1][x]

g[1.]

ff=PDF[PoissonDistribution[1]]

ff[1]

Plot[ff[x],{x,0,10}]

Mean[ff]

Mean[PoissonDistribution[1]]

f[x_] := x^2

f[3]

Plot[f[x],{x,-3,5}]

D[f[x],x]

Integrate[f[x],x]

g[j_,k_]:= n! p1^j p2^k (1-p1-p2)^(n-j-k)/(j! k! (n-j-k)!)

g[1,2]

Sum[i^2, {i,0,10}]

Sum[i^2,{i,0,n}]

Sum[g[j,k],{k,0,n}]

n=3

g[j,k]

p1=.5

p2=.5

g[j,k]

Plot3d[Out[32], [{j,0,3},{k,0,3}]]

PDF[PoissonDistribution[1]][0]

N[(1/E)]

Plot[PDF[PoissonDistribution[1]][x],{x,0,10}]

Variance[PoissonDistribution[a]]

Sum[PDF[PoissonDistribution[1][x]],{x,10,100}]

N[%]

N[Out[44]]

Integrate[Exp[-r x] (l r)^ (a-1) Exp[-l r] l, {r,0,Infinity}]

