Hi can anyone help me with this problem? Would greatly be appreciated.

  1. M → I

  2. ¬ I ∧ L

  3. M ∨ B

Prove: B

closed as off-topic by curiousdannii, Conifold, Eliran, Alexander Gegg, YiFan Apr 27 at 11:46

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question is missing context. Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – curiousdannii, Conifold, Eliran, Alexander Gegg, YiFan
If this question can be reworded to fit the rules in the help center, please edit the question.

  • Hint: you can get B if you get ~M. You can get ~M from 1 and 2. – Eliran Apr 23 at 22:44
  • 2
    Hi, welcome to Philosophy SE. First, we do not know what course you are taking and where you are at in it, hence what rules you are allowed to use. You have to describe that in your post. For example, ¬ I → ¬M follows from 1 by contrapositive, then 2 gives you ¬M by conjunction elimination, and ¬M together with 3 gives you B by a simple instance of resolution, but who knows what your instructor expects. And second, we tend not to do HW for people, but we can help if you describe what you tried. – Conifold Apr 23 at 22:48
  • Oh Im sorry I didnt know. I just have been having a hard time and hoped I can finally see how to crack this problem so I can tackle others and use what I learned here. – Hamish Docherty Apr 23 at 23:22

Use a Proof by Cases (Disjunction Elimination).

|   M → I
|   ¬ I ∧ L
|_  M ∨ B 
|    |_  M         assumption
|    |    :         
|    |    :
|    |    B          for some reason
|    M → B      conditional introduction
|    |_  B         assumption
|    B → B      conditional introduction
|    B               disjunction elimination

Not the answer you're looking for? Browse other questions tagged or ask your own question.