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Solutions Manual (Are they a help or not?)

  1. Aug 27, 2008 #1
    I was wondering what everyone thought of Solutions manuals? Are they really a great help or are they just not necessary for a student? I do sometimes get stuck on questions, and if I keep working at it I will find the answer and feel like I have accomplished a lot. On the other hand sometimes I just use the Solutions Manual (SM) and don't really feel like I learned anything.

    So I was wondering, is it better to use a bit more time and get a better feeling for how to do some questions or just use the solutions manual , try to understand the answer and move on?
  2. jcsd
  3. Aug 27, 2008 #2


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    Solutions manuals are intended for instructors, not for students.
  4. Aug 27, 2008 #3


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    It's best not to rely on Solutions Manuals or the answers in the back of the book.

    In the 'real world', there are no answers in the back of a book.

    Learn and understand how to solve the problem. Learn the theory.
  5. Aug 27, 2008 #4
    Wow that was a fast reply lol. But what about those solutions manuals that come bundled sometimes. As in the Student solutions manuals? Are they also not smart to use?
  6. Aug 27, 2008 #5
    I see, I heard the same statement from my Physics Professor. My question to this statement though is, is there any way of knowing if something is probably correct or somewhat correct. Other than that is using Dimensional Analysis to see if the equations are right.
  7. Aug 27, 2008 #6


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    It depends on what is in these manuals and, to some extent, how much self control you have. If, say, these have just the answers (e.g a number) then of course it is good to use them to check if you have the correct solution. However, if they are full solution manuals, then you have to be careful that you don't get lulled into just copying from the solution manuals and pretending to yourself that you knew what was going on.

    There are ways to check your answers, though it depends on the question. If, say, you are solving a differential equation, then an obvious check would be to subsitute your answer into the original equation. Dimensional analysis is, as you say, another good check in certain situations.
  8. Aug 27, 2008 #7
    Alright great thanks for the help.
  9. Aug 27, 2008 #8
    I think solution manuals are great. I have used them frequently to check my work and also make great study aids for exams. If you use them to just get the answer and not learn anything, its going to show up on your exams.
  10. Aug 27, 2008 #9
    I think solution manuals are great and very important to a student. Checking whether the answers are correct is equally important as doing the questions. If you don't know whether you are doing it the right way, there is no point of doing it.

    It is also extremely important for self-studying.
  11. Aug 27, 2008 #10
    I use student solutions manuals and I think they are really helpful but only if you use it correctly (that is after trying to figure it out yourself for a long time). If you do a problem and look at the solution and realize they are doing something you didn't realize you could do, then go back to the text and review the material. If you find that the error was a simple sign error, then checking the solutions manual can potentially save you hours of work in the long-run and give you more time to work on other problems.

    Many teachers will give problems on tests that are not like the homework problems (i.e. more in depth) so you won't be able to spit back a solution from the solutions manual. You have to know what's going on.
  12. Aug 27, 2008 #11
    One of the main things that I like about solution manuals, is that after completing a problem and checking that you do indeed have the correct answer, but have realized that the solution manual shows a different way to solve the problem than you did. Granted, your method could be just as efficient or more, but it's always nice to know another way to skin a cat.
  13. Aug 27, 2008 #12


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    a solution or two may help a completely clueless student, but in general the gain is in the struggle. it is not important to know all the answers, but to try hard to find them. in this sense solutions manuals are useless and even harmful. and god help an instructor who needs a solutions manual. mine has been a doorstop in my office for the last 20 years or so, never leaving the floor.

    even if i do not know how to do all the problems, if after 45 years I cannot do a problem, does the student really need to know how to do it? i.e should i be assigning problems i cannot do? well maybe, but should i be dishonest enough not to admit that? problems i cannot do are a fun challenge to all concerned.

    but i appreciate the wisdom of chislam's comment. that is indeed a good way to use one, i.e. as a textbook. but mine makes a really good doorstop too. i admit to being slightly hurt when my secretary asked if i wanted one for my course but i know she was just trying to be helpful, and to unburden her shelf.
  14. Aug 27, 2008 #13
    If it's a student-oriented solution manual (e.g., it only contained answers to some but not all of the questions, and for those answers, it provided a detailed explanation), they can be a benefit to a good student who uses it sparingly and only as a last resort or as a check on their worked-out solution. I, however, saw too many students who used it as a crutch instead of a walking stick.

    For the one course I TAed thrice over in grad school, I'd usually use questions from the problems which weren't worked out in the student solutions manual for my quizzes, so my students couldn't simply regurgitate the answer they had seen in the manual.
  15. Aug 28, 2008 #14


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    I think the main point in this thread is that solutions manuals can be helpful or harmful, depending on how they are used.

    I have used student solutions manuals to check my work, and, even if I'm right, I may see a method they used that I did not think of. I was then able to follow their reasoning, applying it to problems that weren't in the manual and ending up solving them very effectively and efficiently and understanding the whole process very well. In this case, I think checking my work in the manual every so often actually increased my ability to solve other problems for that course that weren't in the manual. I think that supplementing my methods with those I saw in the manual every so often helped me to develop my problem solving skills further.

    I also agree that if one only uses the manual to get around actually thinking about problems and working out answers for yourselves and developing strategies for solving problems. Then the solutions manual can be a very harmful crutch.
  16. Aug 28, 2008 #15
    In light of GO1's post, with which I totally agree, does it not make sense then, to give solutions? In books, to tests, etc. Then it is up to the student to use them properly. Look, we agree solutions can be a big help- so why aren't they given? Because some students will not use them correctly? Isn't that their fault then? Why hold back the oter students because of these slackers?
    People have freedom of choice- even the freedom to choose things that will harm themselves, such as smoking.
    Give students solutions.
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