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You are not logged in. #1 20130602 22:32:17
complex numberBy writing the equation in the form show that its roots are please provide a step to step answer to teach me i cant seem to solve #2 20130603 01:20:00
Re: complex numberI am not sure about this because I cannot do the very last bit of trigonometry but this is what I have got so far: Using a right angled triangle in the Argand diagram: Use the rule of multiplying by the complex conjugate pair: Using standard trigonometric results we need this in terms of cot(A/2): I have put in the minus sign in now. Well spotted anonimnystefy. k = 0 is not a solution I agree Stefy, but why does my answer not work for k = 0 ? EDIT: I now can see that cot(0) is not possible. Given that cot X = 1/(tan X) if X=0 then we have a division by zero. Therefore the argument is not valid for this case. Last edited by SteveB (20130603 16:28:32) #3 20130603 02:17:50
Re: complex numberHi SteveB The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #5 20130603 02:55:14
Re: complex numberIn this steps you lose s minus sign: There are 4 solutions. k=0 is not a solution. Last edited by anonimnystefy (20130603 02:59:15) The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #6 20130603 03:00:46
Re: complex numberYes. I agree. If you let k=0 then z = 1 Last edited by SteveB (20130603 03:03:40) #8 20130603 03:04:35
Re: complex numberWell, actually, when k=0, z is not defined (cot(0)=not defined). But, the first troubles with k=0 begin when we take the reciprocal of both sides of "1/z=..." . Last edited by anonimnystefy (20130603 03:05:28) The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #11 20130603 03:29:14
Re: complex number
That is not correct.
You're welcome! Last edited by anonimnystefy (20130603 03:29:43) The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #13 20130603 03:40:49
Re: complex numberOh, sorry. I didn't understand what he wanted to say. And, anyway, using that would be very hard for a hand method. The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment 