Tuesday, December 11, 2012

Confused about some of the Homework

I understood how to do Partial fraction decomposition in class but my answers on the homework made me think I was doing it wrong. The homework was P.277 #6, 16, 20, 22, 45 just in case the other class had different numbers.

For question #16 I found that A multiplied by -1 made it equal to B.

I had the same result for question #20.

The example we did in class had A = -1 and B = 2. Those aren't negatives of each other like the first two questions we had to solve for homework.

Question #22 was different though. A wasn't a negative of B. Instead A = 0 and the entire equation reduced to 1x+3. It reduced to that even if you didn't find B. If either A or B are equal to 0 then could you just reduce the fraction instead?

Question #45 was the only one that didn't seem to have a weird relationship between A and B. I solved it normally and got the right answer after checking.

Overall I understood what to do and checked my answer. The check worked for all of them but I was thrown off because of the relationship of A and B in questions 16, 20 and 22. Is it possible that A can be the same as B or that A times -1 is equal to B? Or could I have possibly done something wrong?

6 comments:

  1. I don't see why that couldn't be true them equaling eachother wouldn't change the x values of the x's you use to set each denomenator to 0. And thus wouldn't affect our asymtotes and therefore leave the graph how it should be. So yeah I wouldn't worry.....I need to learn how to spell some of these math words

    ReplyDelete
  2. Thank you August: Before opening your comment I was prepared to write the same thing. Weld dome!

    ReplyDelete
  3. Khari...Thank you for such keen attention to detail in your work. I will look for some of the same from your cohorts.

    ReplyDelete
  4. For #22 that's really interesting and I think a lot if people will run into that issue on different problems. Now I am wondering about reducing the fraction as well. Also, I had trouble with #6 the other day I'm pretty sure I made a mistake but when I went through to check I only found something that made me more confused.

    ReplyDelete
  5. Mr. Fedirko, do you think we could go over the procedural part of decomposition again?

    ReplyDelete
  6. Thank you Tashi, yes: We'll go over #22 in class and I will be asking everyone to look for patterns that may help generalize these procedures.

    ReplyDelete