Proof questions are nightmares for most student.
There are two way--mathematical induction and complete induction for solving different problem.
However, I find using mathematical induction more often than using complete induction.
What 3 steps I used for proving statements:
First step: Define P(n).
In order to do so, I will read question really carefully to get what kind of P(n) I have to define and what n means in P(n).
Examples:
the square of b is greater than double of itself when b is a natural number greater than 2.
then P(n) would be: sqr(n)>2n.
Second step:Finding base cases for P(n).
For this step, always find the eaziest case but the smallest case that P(n) is true. That u will be able to find the range of n.
Examples:
For sqr(n)>2n.
Find P(n) is true for n=3.
Third step:(most important steps)Induction steps
For mathematical induction using P(n)=>P(n+1) to prove all n is true for P(n)
Examples:
if P(n) is true. then prove P(n+1)
for the examples about just to find the different between sqr(n+1) and sqr(n) is greater than or equal to 2(n+1)-2(n).
Complete Induction has first two similar steps but the third steps will be (P(0),P(1),...P(n)=>P(n+1)) =>P(n).
That is how I did for proof questions using induction method.
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