Arnold F. answered • 04/19/16
Tutor
5
(53)
College Professor & Expert Tutor In Statistics and Calculus
(1) n=1 is obvious
(2) n=2 double angle formula works
(3) n=3 use formula for cos(2x + x)
Then use a proof by strong induction.
Any questions?
Arnold F.
In "regular" induction the inductive hypothesis/proof is "assume P(k) is true" then prove P(k+1) true. The difference in strong induction: the inductive hypothesis/proof is "assume P(j) true ∀ j ≤ k" then prove P(k+1) true.
With cos(nx) to show cos((k+1)x) true you most likely have to do it in cases depending on whether k is odd or even.
Report
04/21/16
Farhad F.
04/21/16