English
Let i ∈ ι and a, b ∈ α_i. The image of Ico(a, b) under Pi.mulSingle i is the interval Ico between Pi.mulSingle i a and Pi.mulSingle i b.
Русский
Пусть i ∈ ι и a, b ∈ α_i. Образ Ico(a, b) под Pi.mulSingle i равен Ico( Pi.mulSingle i a, Pi.mulSingle i b ).
LaTeX
$$$ \\mathrm{image}(\\Pi.mulSingle\, i)( \\mathrm{Ico}(a,b) ) = \\mathrm{Ico}( \\Pi.mulSingle i\, a, \\Pi.mulSingle i\, b ) $$$
Lean4
@[to_additive]
theorem image_mulSingle_Ico (i : ι) (a b : α i) :
Pi.mulSingle i '' Ico a b = Ico (Pi.mulSingle i a) (Pi.mulSingle i b) :=
image_update_Ico _ _ _ _