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You are not logged in. #1 20060306 06:01:53
Unknown ConstantsIn this question I am given the polynomial f(x) = 3x^4 + ax^3 + bx^2  7x  4 and the factor (x  1). I need to find the values of a and b. If I put the factor into the polynomial I get Aloha Nui means Goodbye. #2 20060306 07:40:48
Re: Unknown Constantsrickyoswaldiow, #3 20060306 08:45:41
Re: Unknown ConstantsThat is the question, aye. The other questions give you two factors to work from. Let my type the question exactly as it is written (I've just noticed somthing that I did not see before as it was smudged over with ink!); Aloha Nui means Goodbye. #4 20060306 10:39:49
Re: Unknown ConstantsAh, that would explain it then. Saying something has (x^2  1) as a factor is actually saying it has two different factors  that is, anything that is a factor of (x^21) must also be a factor of the equation you're trying to solve for. Try breaking (x^21) up into its constituent factors and applying them part by part and see if that gets you anywhere. Good luck, and feel free to ask for more help if you get stuck with that. Last edited by fgarb (20060306 10:40:38) #5 20060306 13:55:26
Re: Unknown Constants
How do I do this? I've never seen such a factor before. Aloha Nui means Goodbye. #6 20060306 14:21:24
Re: Unknown ConstantsOne of the factors of x^21 is what you were using before: x1. You should be able to figure out the other one either by division or by trial and error, the answer isn't complicated. #7 20060307 04:57:51
Re: Unknown ConstantsI do indeed know how to find a and b if I have two factors but I really have no idea how to get the second factor. What must I do to x  1 to make x^2  1? Last edited by rickyoswaldiow (20060307 05:07:19) Aloha Nui means Goodbye. #8 20060307 05:08:14
Re: Unknown Constants(x^2  1) / (x  1) = x + 1! Aloha Nui means Goodbye. #9 20060307 05:28:34
Re: Unknown ConstantsGood! IPBLE: Increasing Performance By Lowering Expectations. #10 20060307 05:40:54
Re: Unknown Constants
Nope, no idea Aloha Nui means Goodbye. #11 20060307 05:43:48
Re: Unknown Constantslong division of x^2  1/f(x) just like you said krassi? Last edited by rickyoswaldiow (20060307 05:47:59) Aloha Nui means Goodbye. #12 20060307 05:53:19
Re: Unknown ConstantsGood. but if a=7 and b=1 we get: Last edited by krassi_holmz (20060307 05:55:33) IPBLE: Increasing Performance By Lowering Expectations. #13 20060307 09:42:23
Re: Unknown Constantshow do I divide f(x) by x^21? Aloha Nui means Goodbye. #14 20060307 09:44:23
Re: Unknown ConstantsUsing the difference of 2 squares rule, (x²  1) = (x+1)(x1). Why did the vector cross the road? It wanted to be normal. #15 20060308 08:13:22
Re: Unknown ConstantsI cannot divide 3x^4 + 7x^3 + x^2  7x  4 by x^2  1 directly (not using my method of long division at least). If I divide by (x + 1) I am left with a cubic expression 3x^3 + 4x^2  3x  4. Do I need to divide this by the other factor (x  1)? Aloha Nui means Goodbye. #16 20060308 10:27:33
Re: Unknown ConstantsI went back to this question and tried it out myself. Aloha Nui means Goodbye. #18 20060308 17:43:49
Re: Unknown ConstantsI told you. IPBLE: Increasing Performance By Lowering Expectations. 