Let n in N,n=2k+1,and 1/(a+b+c)=1/a+1/b+1/c. Show that 1/(a^n+b^n+c^n) = 1/(a^n) + (1)/(b^n) + (1)/(c^n) I have tried, but I don't get anything. Can you please give me a hint?

zaiskaladu

zaiskaladu

Answered question

2022-09-27

Let n N , n = 2 k + 1 , a n d   1 a + b + c = 1 a + 1 b + 1 c
Show that 1 a n + b n + c n = 1 a n + 1 b n + 1 c n
I have tried, but I don't get anything. Can you please give me a hint?

Answer & Explanation

tucetiw0

tucetiw0

Beginner2022-09-28Added 12 answers

From the original equation, we get:
a b c = ( a + b + c ) ( a b + b c + c a )
which is equivalent to
a 2 ( b + c ) + b c ( b + c ) + a b ( b + c ) + c a ( b + c ) = 0
( b + c ) ( a + c ) ( a + b ) = 0
Then, obviously any one of the following must hold:
a = b b = c c = a
In any case we can prove the equation
1 a n + b n + c n = 1 a n + 1 b n + 1 c n
with odd n. Since if we take a = b we get
1 ( b ) n + b n + c n = 1 ( b ) n + 1 b n + 1 c n
which is equivalent to
1 c n = 1 c n
and this is true.....
Liberty Page

Liberty Page

Beginner2022-09-29Added 3 answers

Hint
At the first step, show that ( a + b ) ( a + c ) ( b + c ) = 0
Next, show that two of the three numbers are opposite.

Do you have a similar question?

Recalculate according to your conditions!

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?