How do I set Deluge as default Torrent client?

Question

I have an equation:

Y[u_, v_, w_]:=(sin[u] + v*cos[u]*sin[u - w] - v*sin[w]) 

Which needs to be expressed in a specific form:

Y[u_, v_, w_]:=(a*sin[u] + b*sin[2*u] + c*cos[2*u] + d*v*sin[w])

From doing this by hand, I happen to know that:

a=1
b=(v*cos[w]/2)
c=-(v*sin[w]/2)
d=-(3/2)

This particular example is easy to do by hand with trig identities, but for more complicated equations, mathematica could be very useful if the final form of the equation is known. Is there some specific solver function, or a way to use Solve to do this?

For my particular application with a more complicated equation, I have found a few coefficients of the final form by hand, but others are very long and I would like to use mathematica to both check, and finish the rearrangement.

Solution 1

You don't need to install any additional software to change the default program to open a specific archive type. Just open the file manager Nautilus and right click the file. Open Properties and go to the Open with tab. There you choose the default program.

Solution 2

The easiest way is to use Ubuntu Tweak. Click on Administration and than on Manage type file. On your left, choose All, find bittorrent file and replace the default program. (not sure if all the names are correct, because I don't use English language by default)

Comments

[Kamerom]

I'm a newb :) I'm sorry for wasting your time. I got it thanks!

[daniel.reardon]

It looks like the solution for d that you got is the coefficient of v*sin[w] when you don't have the cos[2*u] term.. because expanding the cos[u]^2 in that coefficient is where the cos[2*u] originates from and in doing that, you're left with (3/2). So it's strange that you correctly get the solution for c, but not d... Thanks, I will look at this and be careful with the errors.

[daniel.reardon]

I just realised from what I said above that your answer for d makes sense. It is combining the coefficients of the 2 places that vsin[w] appear i.e. the (3/2)*vsin[w] and -(v*sin[w]/2)*cos[2*u] terms. These become the answer for d. So really, what you want to do to get the answer for d, is d=d-c but is there some way to avoid this before calculating? Otherwise once all of the coefficients are known, you will have to go through by hand, expand them to get the desired form, and then manually check that terms aren't repeated....