1
ut10
·2010-04-30 01:20:12
thanks bhaiya.
2 : 14+24+34+44+.......
62
Lokesh Verma
·2010-04-30 01:23:24
2nd one the first proof is quite boring...
It goes like this:
15-05 = 14
25-15 = 24+23+22+2+1
35-25 = 34+2.33+2232+....
....
....
...
Then add..
62
Lokesh Verma
·2010-04-30 01:43:29
how does that help? I din get ur proof RPF?
1
student
·2010-04-30 01:45:57
second one same as bhaiya
Σ(n5-(n-1)5)+10Σn3-10Σn2+5Σn-15=Σn4
Σn4=(n5)+10Σn3-10Σn2+5Σn-15
1
Sridhar M
·2010-04-30 01:46:48
He found the nth term and the resulting summation is found.
1
student
·2010-04-30 01:47:42
i think bhaiya thought i posted solution for second one
1
ut10
·2010-04-30 07:44:44
find the sum of the series 12 ,40 ,90 ,168 ,280 ,432,.................
62
Lokesh Verma
·2010-04-30 07:50:24
See these:
2x6
4.10
6. 15
8. 21
10.28
12.36
Now try.
1
ut10
·2010-04-30 08:00:49
thanks bhaiya gr8
getting Tn= 2n * (n2+5n+6)/2
by multiplying and then doing summation getting right solution.