Exactly. After expanding and canceling out we have:
7x6 - 21x5 + 35x4 - 35x3 + 21x2 - 7x.
First I divided by (7x). Then I realized (x-1) is a factor (since x=1 is a zero). After long division I have:
(7x)(x-1)(x4 - 2x3 + 3x2 - 2x + 1)
I think I'm very close to solving it. I substituted y= (1-x) in the first equation and expanded. Then I factored that. However I don't know how to factor the last term.
x4-2x3+3x2-2x+1
WolframAplha say it can be factored into (x2-x+1)2. I just need to figure out how to factor that into this...
Homework Statement
Given:
x7 + y7 =1
x + y = 1
Find the integer value(s) of (x-y)2.
Homework Equations
The Attempt at a Solution
I thought of substituting for y and then finding the rational roots but then I realized x and y don't have to be rational numbers for (x-y)^2 to be an...
Homework Statement
To prove the inequality (attached)
Homework Equations
The Attempt at a Solution
I tried factoring out a 2 from each of the even terms in the denominator. This allowed me to cancel out all the terms (odd) on the numerator up to 1005.
Leaves me with...
I forgot to mention that the problem states that it must be proven without using induction. :(
Thanks Sammy :smile:
Does anyone have any other idea or hint that does not involve induction?
Homework Statement
\frac{1^2*3^2*5^2...(2n-1)^2}{2^2*4^2*6^2...(2n)^2}<\frac{1}{2n+1}
Edit: Must be proven without using induction.
Homework Equations
The Attempt at a Solution
I understand the LHS is the same thing as
\frac{(2n-1)!}{(2n)!}
And (2n)! = k!2^k & (2n-1)! =...
Thank you, I finally understand what it means. It may be easy for you but I've never learned permutations or anything like this. This problem is not course material, just something I came across.
Alright that makes sense. Since we can prove that there will always be at least one even factor...
From what Ray said, I gathered that we substitute arrangements of the 2011 numbers. However, if I understand you correctly, you're saying that we substitute the integers themselves. I'm confused...
Edit
An attempt at the problem:
ODD + ODD = EVEN
ODD + EVEN = ODD...
So let's say instead of 2 to 2012 its from 7 to 12. would one possible arrangement be {10,12,9,7,8,11} → 101297811 ? if that's so I'm guessing there are much more possible arrangements of 2 to 2012 than 2012. Yet the product only has up to a2012. So is this some sort of probability question...
Homework Statement
Please see attached image.
Homework Equations
The Attempt at a Solution
I don't understand the problem at all. Can someone explain to me what the problem is stating, more precisely what an arrangement is? An example would be nice. Thanks.