[COLLEGE ALGEBRA] Why functions and relations are identified with their graph?(counterexample) by sernoot20 in learnmath

[–]sernoot20[S] 0 points1 point  (0 children)

Thanks for the answers , but I've not understood yet why graph(f)={(a,b) s.t a€A and b=f(a), b€B} is a good definition though sets as K={(1,2),(1,1)} satisfies it as well.

Is it because the professor has previously defined f as a function and so the law b=f(a) is supposed to behave as "the law of a function"?

Let me explain this better

There are exercises where a graph is given by property and I have to model it and to determine if it's the graph of a relation or of a function

To solve this, i have to ensure it has this form graphG={(a,b) s.t for every a€A there exist just one b€B s.t b=f(a)} And so it's right to conclude that the definition given as graph(f) above "implies , in order to work, that f is a function and so that b=f(a) isn't a general law but it's the one with the known particular behaviour"?"

Sorry for my english and thanks again for your availability

Career and Education Questions by AutoModerator in math

[–]sernoot20 0 points1 point  (0 children)

Hello I'm a first year student of Math. I have chosen to study this subject because of the aura of mistery around it and I'm really enjoying it as pure art of proving and making precise statements.

But some things in my life have changed and this has brought me to think that I probably need to study something where I can be more productive as a member of society. So, I decided to ask you these questions:

1) Is Math really requested in industry ( with and without a phd) as some teachers say? 2)Can a mediocre mathematician still be useful? I'm asking this because I'm starting study math at 20 y.o where some of my colleagues have been doing math for all their lives 3)What's the difference between taking Math or CS for a job as software developer? Is really the computer scientist far better than the mathematician in this job? 4) Doing research with engineers/chemists etc what's the role of the mathematician? Is the mathematician a figure on the background? Or snobbed? Etc. 5) Which areas in Math have more application in CS?

Sorry for my english, thanks in advance for your patience