English
If hf : HasFDerivWithinAt f f' s x and hg : HasFDerivWithinAt g g' s x, then HasFDerivWithinAt (fun x => f x − g x) (f' − g') s x.
Русский
Если hf : HasFDerivWithinAt f f' s x и hg : HasFDerivWithinAt g g' s x, тогда HasFDerivWithinAt (fun x => f x − g x) (f' − g') s x.
LaTeX
$$HasFDerivWithinAt (f − g) (f′ − g′) s x$$
Lean4
@[fun_prop]
nonrec theorem sub (hf : HasFDerivWithinAt f f' s x) (hg : HasFDerivWithinAt g g' s x) :
HasFDerivWithinAt (f - g) (f' - g') s x :=
hf.sub hg