tag:blogger.com,1999:blog-10220498.post3143327533618026432..comments2023-06-01T10:31:54.272-05:00Comments on Math Teacher Mambo: Piecewise FunctionsShireen Dadmehrhttp://www.blogger.com/profile/16282965851939089408noreply@blogger.comBlogger7125tag:blogger.com,1999:blog-10220498.post-40959784095308152082011-10-13T09:31:28.176-05:002011-10-13T09:31:28.176-05:00My middle range students have been struggling with...My middle range students have been struggling with the Algebra basics, like point-slope and such. I think they began to understand when I explained that the point-slope form comes from the slope formula (which most of them know REALLY well). I showed them that in the slope formula, if you multiply each side by the (x2-x1), you get m(x2-x1)=y2-y1. Since there are three parts to the slope formula (one of which is always missing): slope, point1 (x1,y1), and point2 (x2,y2), when we have two points we use m = (y2-y1)/(x2-x1) because we are missing the m. When we have one point and a slope, the second point is missing that's why it's just x & y not x2 & y2.<br /><br />That seemed to clear up the point-slope for a bunch more of them. <br /><br />As for the piecewise, THANK YOU! I have been looking for more examples to explain to them.pmorourkenoreply@blogger.comtag:blogger.com,1999:blog-10220498.post-29858491014708739462007-10-01T16:51:00.000-05:002007-10-01T16:51:00.000-05:00Great idea! I'm excited to try this in my algebra...Great idea! I'm excited to try this in my algebra II class. Thanks for the idea.jen4asahttps://www.blogger.com/profile/03593466418847896624noreply@blogger.comtag:blogger.com,1999:blog-10220498.post-51936888556215974512007-09-25T07:07:00.000-05:002007-09-25T07:07:00.000-05:00Thank you sooo much!! You just saved my grade!!!Thank you sooo much!! You just saved my grade!!!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-10220498.post-37918457321768363462007-09-12T18:27:00.000-05:002007-09-12T18:27:00.000-05:00I like your idea of capitalizing the constants or ...I like your idea of capitalizing the constants or "things" that are replaced with numbers. That's a good visual. I think I'll start adding that to my repetoire. Thanks.<BR/><BR/>I have to get my kids ready for next year and the AP exam where some of the answers are given in point slope form, so that's why I'm stressing it.<BR/><BR/>Ms. CookieAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-10220498.post-44242490589629510602007-09-12T16:00:00.000-05:002007-09-12T16:00:00.000-05:00i tend to play down the point-slope formto the ext...i tend to play down the point-slope form<BR/>to the extent of: "it's there in the text<BR/>and if you know it already <BR/>or want to learn it, by all means<BR/>feel free".<BR/><BR/>but that's just because my students--<BR/>college students with weak math backgrounds--<BR/>struggle hard enough with slope-intercept<BR/>that the added burden of a special-purpose<BR/>formula doesn't seem worth it.<BR/>better to spend more time on getting<BR/>*one* thing understood well<BR/>than just pile on confusion<BR/>in the name of "coverage".<BR/><BR/>obviously, with more capable students<BR/>(or more time in the quarter ...<BR/>a semester's worth, say ...)<BR/>i'd very likely act differently.<BR/><BR/>one issue that arises frequently:<BR/>"x" and "y" *stay* "x" and "y"<BR/>while "x_1" and "y_1" are replaced<BR/>with numerical values.<BR/>this shouldn't be confusing,<BR/>but it is.<BR/><BR/>i like to capitalize --<BR/>yes, believe it or not --<BR/>constants (e.g. y = Mx+B)<BR/>and wish this were an industry standard.r. r. vlorbikhttps://www.blogger.com/profile/02746118913980983815noreply@blogger.comtag:blogger.com,1999:blog-10220498.post-65578736876815090822007-09-09T15:51:00.000-05:002007-09-09T15:51:00.000-05:00Yea! I don't exactly remember, but I believe you c...Yea! I don't exactly remember, but I believe you can get it done in one class period (48 minutes or so). I had block scheduling, and we did some review before hand.<BR/><BR/>Good luck,<BR/><BR/>Ms. CookieAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-10220498.post-71973455279741335762007-09-09T15:36:00.000-05:002007-09-09T15:36:00.000-05:00Great idea! I'm stealing this as we're starting p...Great idea! I'm stealing this as we're starting piecewise functions soon!<BR/><BR/>I too just experienced "reintroducing" the point slope form. Not sure why the students don't seem to like it.Anonymousnoreply@blogger.com