Did I prove this right? (1 Viewer)

[calamebe]

Hey i have a proof but I'm doubting how true it is. Also would like any other methods, but mainly can someone say my proof is valid or not. Here the proof: http://m.imgur.com/a/fuQ9F
Thanks

Edit: Oh, and also the question for some reason is below the proof, must've uploaded it wrong. But the question is in the album.

 

[Thjv]

http://imgur.com/wFEFF5r

 

[calamebe]

http://imgur.com/wFEFF5r

Thanks for the alternate method, do you know if mine is true though? There are multiple ways to prove one thing.

 

[Carrotsticks]

Looks good except:

- In your 5th line (the lone equal sign), you forgot to get rid of the +pi when turning it into -r^3 cis(3 theta).

- Best that z_2 should be r cis (theta plus/minus pi/3), since to form the equilateral triangle you can rotate either clockwise or anticlockwise. Proof doesn't change either way.

 

[calamebe]

Looks good except:

- In your 5th line (the lone equal sign), you forgot to get rid of the +pi when turning it into -r^3 cis(3 theta).

- Best that z_2 should be r cis (theta plus/minus pi/3), since to form the equilateral triangle you can rotate either clockwise or anticlockwise. Proof doesn't change either way.

Thank you, just a couple silly mistakes as usual haha.

 

[axwe7]

Are you doing a double accelerated math course?

 

[calamebe]

Are you doing a double accelerated math course?

I am accelerated by one year in 3U and 4U. So I'm in your year for most stuff, but the grade above for maths.

 

[axwe7]

I am accelerated by one year in 3U and 4U. So I'm in your year for most stuff, but the grade above for maths.

Oh okay..

Because in your signature it says that your doing the 4U HSC next year, whilst your also doing your prelim subjects...

But I get it now..

So I'm guessing you probably go to Sydney Boys or Penrith?

 

[calamebe]

Oh okay..

Because in your signature it says that your doing the 4U HSC next year, whilst your also doing your prelim subjects...

But I get it now..

So I'm guessing you probably go to Sydney Boys or Penrith?

Nope, schools around rank 300. Got a friend doing the same thing though, and someone did it in the year above me. It's weird.

 

[leehuan]

A tad insulted. You don't have to go to a top ranking school to be accelerated ._.

 

[kawaiipotato]

A tad insulted. You don't have to go to a top ranking school to be accelerated ._.

Wish my school offered accelerated

 

[axwe7]

Wow...And all this time I was wondering that only top notch ranking schools offer accelerated...

Good on you calembe!

Wish I were in your place.

 

[leehuan]

Wish my school offered accelerated

At my Yr 11-12 school though, I think that's the only time they'll ever have offered acceleration.