Prove this by MI.
∑_(r=1)^3▒1/3^r = 1/2 - 1/(2(3^n))
How do I display this properly? I write from MS words and paste here. I try wrapping with Math tag but it wont work.
We proceed by mathematical induction.
Let for all
is true, since
Assume is true, we now show that this implies is true.
Since is true, we have
Then
.
.
.
i leave it to you to finish up. my last line was a crucial hint
see hereHow do I display this properly? I write from MS words and paste here. I try wrapping with Math tag but it wont work.