This is the book currently used in top-tier high schools to learn calculus. It is highly accessible. It creates a spark, at least in me, that made me take that book to bed and learn so much all night.
You'll get lots of practice if you do their practice problems (especially the more complex and involved ones later). Calc 3 is also covered in this book.
It's commonly used for introductory Astrophysics courses. If you don't have a basic understanding of Calculus it won't make much sense so, if you really want to properly understand the subject, first study basic Calculus. A good introductory Calculus book would be this one:
Those three books together should give you a basic understanding of Astrophysics and put your feet solidly on the road to further understanding. Read the Calculus book first (at least the first half of it or so) and then the Physics book. Then you'll be ready to dive into Carroll and Ostlie's book!
If you don't want to go quite that deep and you just want a really basic overview of the subject, you might consider finding Hawking's "A Briefer History of Time" or watching the PBS SpaceTime series in YouTube.
Edit: If the Calculus book is still a little unclear, your issue probably lies in Algebra. In that case, read this book before any of the others:
If the "Early Transcendentals" book does not have "Single-Variable" or "Multi-Variable" in its name, then it has all of the content of both books; if it does have "Single-Variable" in its name, then it might share a chapter with "Multi-Variable" but that's it.
The response by /u/jimmy_rigger was made as if you were asking about a textbook explicitly labeled as "Single-Variable", and my reply pointed out that you weren't.
---
You can look inside the books to see for yourself:
I even noticed almost the same sequence of chapters in a competing textbook (Thomas), except that it puts infinite series before polar/parametric (chapters 10 and 11).
Download this book illegally: https://www.amazon.com/Calculus-James-Stewart/dp/1285740629
This is the book currently used in top-tier high schools to learn calculus. It is highly accessible. It creates a spark, at least in me, that made me take that book to bed and learn so much all night.
You'll get lots of practice if you do their practice problems (especially the more complex and involved ones later). Calc 3 is also covered in this book.
An Introduction to Modern Astrophysics is an excellent and easy to read book:
https://www.amazon.com/dp/1108422160/ref=cm_sw_r_cp_apa_omrWBbDYB9MN3
It's commonly used for introductory Astrophysics courses. If you don't have a basic understanding of Calculus it won't make much sense so, if you really want to properly understand the subject, first study basic Calculus. A good introductory Calculus book would be this one:
https://www.amazon.com/dp/1285740629/ref=cm_sw_r_cp_apa_JdsWBbH1KXPAN.
You're also going to want a basic understanding of Physics so one more for that:
University Physics with Modern Physics (14th Edition)
https://www.amazon.com/dp/0321973615/ref=cm_sw_r_cp_apa_LfsWBbHJ83MT6
Those three books together should give you a basic understanding of Astrophysics and put your feet solidly on the road to further understanding. Read the Calculus book first (at least the first half of it or so) and then the Physics book. Then you'll be ready to dive into Carroll and Ostlie's book!
If you don't want to go quite that deep and you just want a really basic overview of the subject, you might consider finding Hawking's "A Briefer History of Time" or watching the PBS SpaceTime series in YouTube.
Edit: If the Calculus book is still a little unclear, your issue probably lies in Algebra. In that case, read this book before any of the others:
College Algebra (10th Edition)
https://www.amazon.com/dp/0321979478/ref=cm_sw_r_cp_apa_MqsWBbR985C30
Good luck on your journey! Give yourself at least a year or two to get through all of them and don't forget to work the problems!
Oh - download Kerbal Space Program and play it for a while. Trust me on this; you'll develop a second sense of basic orbital mechanics ;)
Math texts are among the most egregious examples of unnecessarily updated texts. Almost none of the math you'll learn as an undergrad has changed in my lifetime, but students have to buy the newest version just so they can have the right homework problems. Stewart's text is at version 8, and you can [buy it on Amazon for $183] (https://www.amazon.com/Calculus-James-Stewart/dp/1285740629/ref=pd_sbs_14_1?_encoding=UTF8&pd_rd_i=1285740629&pd_rd_r=JVSPPXJ3JZSTMBTMY7ZA&pd_rd_w=y7iOT&pd_rd_wg=2XT4J&psc=1&refRID=JVSPPXJ3JZSTMBTMY7ZA). I just looked and found a used copy of the 7th edition for $12. It's so cheap because student's cant use the damned thing. I used Thomas and Finney's book thirty years ago, and there haven't been any developments in Calculus since then that are relevant to a Freshman Engineering Major. The teacher of my Functional Analysis class in grad school was fed up with this, so we used Riesz and Sz.-Nagy's Dover Edition. This was a graduate-level math class, and we were able to use a text that was decades old.
https://www.amazon.com/Calculus-James-Stewart/dp/1285740629/ref=sr_1_1?ie=UTF8&qid=1484794699&sr=8-1&keywords=calculus+8th+edition
This is what my school requires of us. https://www.amazon.com/gp/aw/d/1285740629/ref=mp_s_a_1_1?ie=UTF8&qid=1501294155&sr=8-1&pi=AC_SX236_SY340_FMwebp_QL65&keywords=calculus+stewart+8th+edition
Don't forget the $130 Web assign!
If the "Early Transcendentals" book does not have "Single-Variable" or "Multi-Variable" in its name, then it has all of the content of both books; if it does have "Single-Variable" in its name, then it might share a chapter with "Multi-Variable" but that's it.
The response by /u/jimmy_rigger was made as if you were asking about a textbook explicitly labeled as "Single-Variable", and my reply pointed out that you weren't.
---
You can look inside the books to see for yourself:
I even noticed almost the same sequence of chapters in a competing textbook (Thomas), except that it puts infinite series before polar/parametric (chapters 10 and 11).
https://www.amazon.com/Calculus-James-Stewart/dp/1285740629/ref=sr_1_2?ie=UTF8&qid=1466199140&sr=8-2&keywords=james+stewart+calculus+8th+edition
It covers Calculus 1-3. I have a downloaded version from a friend of the whole book.