Asked by Passband Modulation
on 5 Oct 2012

it is really tedious, probably impossible, to do the following equation using a calculator. Please note that cosine and sine functions are in degrees

the result should b a scalar value if i am right?

*No products are associated with this question.*

Answer by Walter Roberson
on 5 Oct 2012

Accepted answer

k = 0:65119; sum( cosd(3.6*k) .* sind(3.6*k) ).^2

Passband Modulation
on 5 Oct 2012

cool, it really works. actually, i just manage to obtain the result using

function [S] = sum1(n) S = 0; % Initialize sum to zero k = 0; % Initialize index to zero % loop for calculating summation while k <= 65119 S = S + cos(3.6*k*pi/180)*sin(3.6*k*pi/180); % add to summation k = k + 1; % increase the index end

and then square the outcome, and get the answer as urs.

cool, urs looks tidier. many thx

MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi test

Learn moreOpportunities for recent engineering grads.

Apply Today
## 3 Comments

## Walter Roberson (view profile)

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/49932#comment_103193

The equation seems to be missing from your Question ?

http://www.mathworks.com/matlabcentral/answers/7924-where-can-i-upload-images-and-files-for-use-on-matlab-answers

## Walter Roberson (view profile)

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/49932#comment_103197

I see you have changed the wording of your question a little, and given the note about degrees, but the equation itself isn't there yet ?

## Passband Modulation (view profile)

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/49932#comment_103198

sry, i just reuploaded the image, could you now see the equation?