(* Задача 1. *)
(E^π)>(π^E)

(* Задача 2. *)
RegionPlot[((x^2)/4)+((y^2)/9)≤1,{x,-4,4},{y,-4,4}]

(* Задача 3. *)
f[x_]:=3(x^4)-8(x^3)+6(x^2)-3x-4;
g[x_]:=(x^3)+1;
Solve[f[x]==0,x]

NSolve[f[x]==0,x]

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

h[x_]:=((f[x])/(g[x]));
a=Limit[((h[x])/x),x->∞]

b=Limit[h[x]-a*x,x->∞]

y[x_]:=a*x+b

(* Задача 4. *)
A=Table[Table[Abs[i-j],{j,1,5}],{i,1,5}];
MatrixForm[A]

Det[A]

N[Eigenvalues[A]]

N[Eigenvectors[A]]

inverseMatrixA=Inverse[A];
MatrixForm[inverseMatrixA]