# Plz help me about online PDFs

There are many PDFs (Portable Document Formats) of many math or physics books available in online. But I am not sure whether those are legal/authorized or not. If they aren't, then the readers of these PDFs (Books) are just reading these without paying for the authors' hard work. I would feel really bad to do that. So, my questions to you guys are: $$1.$$ Are these PDFs legal/authorized? $$2.$$ If they aren't, where can I learn math and physics best? Pleeeze give me as much 'best weblinks for learning math and physics' as you can. $$3.$$ If only some of them are legal, is there any way to find which of them are legal? If you guys know about such PDFs, then pleeeze give me the links. Thanks in advance.

Note by Aiman Rafeed
4 years, 10 months ago

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Here you have a very cool book about tools of Algebra, it was my book guide in the University (1rst course). It's quite complete. The problem is that it is in Spanish, but it's a book very logical, you need read it sometimes before you start to understand it. I hope it helps you and likes you Algebra básica. I can also lead you in other disciplines with good books, what are you interested about? You can find a lot free legal books here

- 2 years, 3 months ago

Thanks a lot! The link to legal books will help a lot. As for "Algebra Basica", I really have no knowledge of Spanish. Grassias means thanks - that, I know...haha. Interests: All of math, but I specially like Calculus, Combinatorics & Geometry. I like physics as well.

- 2 years, 3 months ago

you're welcome, ok, I'll try to find good books in English about these one, in my last link you can search... Look a view at this: Introduction to Probability

Anyway, you'll have to work very hard if you want to be a good student... I'll continue researching, greetings.

- 2 years, 3 months ago

- 2 years, 3 months ago

many of them are legal, and many of them are illegal too, and also many of them are free.

why don't you visit The Ultimate Free Encyclopedia which we called it Wikipedia.org, and then build your own book and export to PDF format. isn't the same?

- 4 years, 10 months ago

This is a good strategy. I wasn't doing this all this time because whenever I went to wiki, I had this terminology problem...didn't understand most of the math or physics terminologies. So studying from wiki is a hard and lengthy thing (I think). Yet your suggestion let me think another time about it and I think I'll do it. Thanks a lot.

- 4 years, 10 months ago

great book always hard to understand because their complexity and also hard to forget because they teach knowledge not just the shortcut.

and you must stay critical because many articles (40%-60%) on wikipedia just have truth accuracy between 60%-80%. so many mistake on their articles, but level of their mistake is 80%-90% professor level, then don't worry so much and just stay critical.

happy critical thinking :)

- 4 years, 10 months ago

legal

- 4 years, 10 months ago

Are you sure? Most of them or all of them? If not all of them then which of them? Note that Diganta has said these aren't legal. Sorry if I'm annoying u guys. But I really must know it. Thanks a lot.

- 4 years, 10 months ago

sobkota legal noe mane eigulo taka diye kena jaye

- 4 years, 10 months ago

@ Olih P, I see. Thanks.

- 4 years, 10 months ago

no

- 4 years, 10 months ago

Hi Diganta, apni math are physics shikhen kotha theke? Amake koekta link are boier num bolte parben? Thanks again.

- 4 years, 10 months ago

parben bolo na bolo parbe tumi dada ho(o).boier nam tumi aager discussion gulo search korle peye jabe diye google it

- 4 years, 10 months ago