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#76 Science HQ » mirrors #2 » 2014-04-20 03:37:58
- gourish
- Replies: 6
if two mirrors are placed at angle θ to each other then find the number of images formed by an object placed in between them....
i just found that the number of images(n) is given by n=[360/θ] for n being even and [360/θ -1] for n being odd and [.] is the greatest integer function but i don't know how this was derived
#77 Re: Science HQ » root mean square value » 2014-04-20 03:34:38
actually i didn't find the omega symbol which is generally used for the angular frequency of a wave so i used so treat it as a constant....
#78 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 03:31:13
hmm... so what's the need for using the interpolation formula..i have enough data to plug into the cubic myself and find the answer... it's really to unnecessary formula don't you think so?
#79 Science HQ » mirrors... » 2014-04-20 03:23:19
- gourish
- Replies: 8
if a pair of mirrors are placed together making an angle θ with each other and if a ray of light parallel to first mirror reflects from the second mirror which after 2 successive reflections becomes parallel to second mirror. then find the angle θ
#80 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 03:18:41
i did not understand the l 2 and l 3 part and sorry i still couldn't understand how it was derived
#81 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 03:15:10
i will go through them again and try to understand how it was derived....
#82 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 03:12:57
no i am sorry the signs used are quite complicated for me. i never really came across these before...
#83 Science HQ » root mean square value » 2014-04-20 03:11:31
- gourish
- Replies: 14
if current i=3 sin Δ t + 4 cos Δ t
then the root mean square value of current is....
can anybody tell me a way to answer this using either calculus or a rough graph?
#84 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 03:04:36
yeah it kicks out the mystery of things in finding the solution thanks 
#85 Re: Help Me ! » trigonometry#3 » 2014-04-20 03:01:14
hi Niharika can you please use the latex code for your expression cause the question seems quite clear and i did get sinθ=cos^3 θ
use the G.M. formula if tanθ is the G.M. between sinθ and cosθ then tanθ=sqroot(sinθ*cosθ) then u easily get sinθ=cos^3 θ so just post the expression clearly so we can work it out
#86 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 02:53:26
i would rather hit my head on the desk then use this formula... it's better to guess on the answer from the choices....
#87 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 01:05:45
okay i can wait.. you take your time and post....
#88 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 01:01:23
ok yeah let's go with the smaller one then....
#89 Re: Help Me ! » the summation of series » 2014-04-20 00:50:11
ok cool thanks
#90 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 00:48:22
Compute f(0.3) for the data
x
0
1
3
4
7
f
1
3
49
129
813
using Lagrange's interpolation formula (Analytic value is 1.831)
this is what i found on the net. can you show me how to find answer to this question using Lagrange's formula
reference for the actual question :http://mat.iitm.ac.in/home/sryedida/public_html/caimna/interpolation/lagrange.html
#91 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 00:46:47
yeah that's what i want to learn....
#92 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 00:44:15
but can you just show me how to use it with an example
#93 Re: Help Me ! » the summation of series » 2014-04-20 00:43:10
okay so i still need to use my calculator to end up with an answer
#94 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 00:40:52
ok i get it.. but does it mean that it's the other way of saying "look there is a relation between two sets and i can get so and so number of functions out of the relations set"?
#95 Re: Help Me ! » the summation of series » 2014-04-20 00:36:22
so you still end up having another function but no actual answer in terms of numbers?
#96 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-20 00:21:54
yeah for sure.... quite excited to see it
#97 Re: Help Me ! » the summation of series » 2014-04-20 00:16:34
can you elaborate on harmonic number i went through Wikipedia it's just mind boggling is there any simple way to use this harmonic number to find the sum of such series?
#98 Re: Help Me ! » Lagrange's interpolation polynomial » 2014-04-19 21:31:39
yeah only that... plus i don't know what the Lagrange's interpolation formula is... so can you help me with that
#99 Re: Help Me ! » the summation of series » 2014-04-19 21:30:14
but what if i just to find the sum of the series from 1 to n where n belongs to natural numbers... it's basically from a series summation problem.... where the limits are not infinity but some finite value n but thanks for the help can you help me find that sum of 1/i and 1/i^2 for
i=1 to n
#100 Help Me ! » the summation of series » 2014-04-19 18:26:51
- gourish
- Replies: 11
i find it easy to find the sum of series of numbers raised to powers but when i need to find the sum of series like 1/n or 1/n^2 and so on it becomes tough i googled it but didn't find any satisfactory way to find such sum of series. so can anybody help me and please explain how to find those formula i don't like a list of formula which i will never remember