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This is a technique
that is all too often
overlooked in geometry. I include it here for completeness. Suppose P(n) is
a sentence which is a statement for any
, then the Principle of
Mathematical Induction is

If we
can prove the antecedent of this statement,
, then by Modus ponens we can deduce
. Thus there are two steps in the proof of
:
- Basic Step.
- Prove P(1).
- Inductive Step.
- Prove
.
Note that its name is misleading. Mathematical induction is
deductive reasoning not inductive reasoning. Inductive
reasoning is making a conjecture or guess based on observations and your
previous mathematical experience.
droyster@math.uncc.edu