tag:blogger.com,1999:blog-5964889903484807623.post3145295017349384887..comments2021-05-11T07:20:00.591-07:00Comments on Questions?: Standard DeviationDavid Coxhttp://www.blogger.com/profile/06277427735527075341noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-5964889903484807623.post-59458407613418763122010-05-20T08:32:46.825-07:002010-05-20T08:32:46.825-07:00Teacher or Student? Thanks for stopping by; I'...<b>Teacher or Student?</b> Thanks for stopping by; I'm glad you're finding this blog helpful. <br /><br />I'll check out your rule...thanks.David Coxhttps://www.blogger.com/profile/06277427735527075341noreply@blogger.comtag:blogger.com,1999:blog-5964889903484807623.post-72982076200414665862010-05-17T22:05:18.684-07:002010-05-17T22:05:18.684-07:00I've been reading your blog for a while, but t...I've been reading your blog for a while, but this is my first post. Just wanted to let you know that I'm enjoying and learning.<br /><br />@Calc Dave: I think of "never do any math" as don't simplify. "Simplifying" is actually one of my pet peeves and I try my best to never use the term (although I sometimes fail because it is quite ingrained). Instead I talk about different forms and the form for the context that is most informative. So in your case, 2+1+2+3 is much more informative than 8. <br /><br />@David: You mentioned that your students were looking for a different pattern that worked for your 3rd sequence. It's ugly, but if you consider 1 to be the 0th term, (1/3)(590x^3-1770x^2+1210x+3) works. I'd give you the "unsimplified" expression, but that would take away all the fun of how I figured this out. :)Avery Pickfordhttps://www.blogger.com/profile/10433339146333801163noreply@blogger.comtag:blogger.com,1999:blog-5964889903484807623.post-36736835123977128992010-04-23T17:57:14.403-07:002010-04-23T17:57:14.403-07:00To be honest, I've never really gotten into th...To be honest, I've never really gotten into the notation in sequences with my 7th graders. Most of what happend in this lesson just kinda happened. I saw where they were taking it, I liked it and we went with it. <br /><br />I like what you describe. Re-writing the terms using what they all have in common will make defining a variable much easier. Thanks.David Coxhttps://www.blogger.com/profile/06277427735527075341noreply@blogger.comtag:blogger.com,1999:blog-5964889903484807623.post-9964501371938604842010-04-22T15:03:32.316-07:002010-04-22T15:03:32.316-07:00Maybe you do this already with sequences, but what...Maybe you do this already with sequences, but what I tell the students that helps them "see the light" on writing formulas (recursive or not) is that they should NEVER do any math once they see the pattern. So, your first sequence would end up being 2, 2+1, 2+1+2, 2+1+2+3, ... Once you break it down into the pattern, then it's much easier to connect the subscript to the current term, I think.<br /><br />I also like the "Give two possible answers for the next number in the sequence given the pattern for the first four" problem. I end up telling them that if you are only given a finite number of terms in a sequence, you can NEVER definitively say what the next term will be. Even 1, 2, 3, 4, ... could be a sequence that continues to just repeat 1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4, ... and you just happened to stop at the worst time possible.CalcDavehttps://www.blogger.com/profile/14039458440867020542noreply@blogger.com