English
The operator norm of the composed multilinear map is at most the product of the op-norms of the involved maps.
Русский
Норма оператора композиции много-линейного отображения не превосходит произведения норм оператора вовлечённых отображений.
LaTeX
$$$ \|g.mkContinuousLinear f C H\| ≤ \|g\| \cdot \prod_i \|f_i\| $$$
Lean4
theorem norm_compContinuousMultilinearMap (g : G →ₗᵢ[𝕜] G') (f : ContinuousMultilinearMap 𝕜 E G) :
‖g.toContinuousLinearMap.compContinuousMultilinearMap f‖ = ‖f‖ := by
simp only [ContinuousLinearMap.compContinuousMultilinearMap_coe, LinearIsometry.coe_toContinuousLinearMap,
LinearIsometry.norm_map, ContinuousMultilinearMap.norm_def, Function.comp_apply]