Question

proof

Answer 1

@jhonyy9

Answer 2

i think its part of the problem how they defined it?

Answer 3

\(\color{#0cbb34}{\text{Originally Posted by}}\) @jhonyy9
how come there this a ?

\[a \in \R]
\(\color{#0cbb34}{\text{End of Quote}}\)

Answer 4

i found an online solution but can you explain it by detail

Answer 5

do you can post it here ?

Answer 6

thats a solution that i found online

Answer 7

from what you founded online

but first of all given that f(x+y) = f(x) +f(y) for all x,y in R

from this given result f(x+x) = f(x) +f(x) = 2f(x) for x in R
and you know f(x) = f(x-c) +f(c) for x,c in R

Answer 8

the proof you found online has some mistakes. and what johnny mentioned has no relevance to the question also it seems.

the "forward if" is somewhat correct like (3/10). but the "backward if" is not so. It has rather a trivial proof.

Answer 9

can you please show me , how you would write the proof

Answer 10

\(\color{#0cbb34}{\text{Originally Posted by}}\) @aquire
and what johnny mentioned has no relevance to the question also it seems.

\(\color{#0cbb34}{\text{End of Quote}}\)
@ Hero:All the information necessary to solve the solution is there.

Ah I see that now. Sorry @ johnny you were right. But I still think there are some mistakes in the online proof though. If the OP is interested I'll be happy to help.

Answer 11

\(\color{#0cbb34}{\text{Originally Posted by}}\) @xXMarcelieXx
can you please show me , how you would write the proof
\(\color{#0cbb34}{\text{End of Quote}}\)
Will do

Answer 12

thank you, please do :)

Answer 13

Do you know the epsilon delta definition of limits?

Answer 14

yes, i can post the defintion

Answer 15

I think the best way would be to use that definition. But since the online proof is what you're familiar with I'll just correct its mistakes and do the proof, ok?

Answer 16

okie

Answer 17

I do not see why you need to use the hint. Without hint you can do it. Maybe I am wrong idk

Answer 18

ty

Answer 19

yw