Algebraic Limit Theorem for Functional Limits

Let f,g:A→R where A⊆R and c is a Limit Point of A. Let L,M∈R. If:

limx→cf(x)=L,limx→cg(x)=M

then:

  • limx→c[αf(x)]=αL for all α∈R.
  • limx→c[f(x)+g(x)]=L+M
  • limx→c[f(x)g(x)]=LM
  • limx→cf(x)g(x)=LM provided M≠0.

Proof

Use the Sequential Criterion For Functional Limits, but now using the Limit Laws (Algebraic Limit Theorem) for sequences for each.

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