simpler example for randn

stdlib/Random/src/normal.jl

@@ -23,8 +23,33 @@ from the circularly symmetric complex normal distribution of variance 1 (corresp
 See also [`randn!`](@ref) to act in-place.
 
 # Examples
+
+Generating a single random number, by default of type `Float64`:
+
+```julia-repl
+julia> using Random
+
+julia> randn()
+-0.942481877315864
+```
+
+Generating a matrix of normal random numbers, by default of type `Float64`:
+
+```julia-repl
+julia> using Random
+
+julia> randn(2,3)
+2×3 Matrix{Float64}:
+  1.18786   -0.678616   1.49463
+ -0.342792  -0.134299  -1.45005
+```
+
+Setting up of the random number generator with a user-defined seed, and the generation of a random `ComplexF64` number, or a matrix `ComplexF32` normal random numbers:
+
 ```jldoctest
-julia> using Random; rng = Xoshiro(123);
+julia> using Random
+
+julia> rng = Xoshiro(123);
 
 julia> randn(rng, ComplexF64)
 -0.45660053706486897 - 1.0346749725929225im