English
If SemiconjBy a x y and SemiconjBy b x y, then SemiconjBy (a+b) x y.
Русский
Если SemiconjBy a x y и SemiconjBy b x y, то SemiconjBy (a+b) x y.
LaTeX
$$$ (SemiconjBy a x y) \land (SemiconjBy b x y) \Rightarrow SemiconjBy (a+b) x y $$$
Lean4
@[simp]
theorem add_left [Distrib R] {a b x y : R} (ha : SemiconjBy a x y) (hb : SemiconjBy b x y) : SemiconjBy (a + b) x y :=
by simp only [SemiconjBy, left_distrib, right_distrib, ha.eq, hb.eq]