DOHVOHQC JSGAY M AV SO 8 201 l i ''''• '''' iJ* r''''«s^ 41 Van dung day hpc pliat liien va giai quyet van d€ trong liinh thanh phep nhan so thap phan of lofp 5 TtiS PHAM VAN CONG TrUdng TH Van Cam, HUng Ha,[.]
DOHVOHQC SO 8-201 l i JSGAY 'ã '.iJ* r'ôs^ M.AV 41 Van dung day hpc pliat liien va giai quyet van d€ liinh phep nhan so thap phan of lofp TtiS PHAM VAN CONG TrUdng TH Van Cam, HUng Ha, Thii Binh P hit huy tfnh tfeh cue hpc tap ciia hpc sinh la mdt van de da dupe dat eho nginh giio due tU nhieu nam v i da trd thinh mdt nhQng phQdng hUdng chfnh cdng cupe doi mdi giio due Tuy nhien de dat dUdc dilu dd thi v l n edn khdng it khd khan ddi vdi mdi giio vien, dac bidt l i giio vidn tilu hpc bdi nhQng phUdng phip day hpc truyen thdng da ngim sau vio tam tUdng eiia nhieu ngUdi Trong sU nghiep doi mdi eiia dat nUde hien nlu cQ tiep tue day theo Id'i dge-chep, hpc sinh hoan toan thu dpng vao giao vidn nhu t h i se khdng dap Qng dUde yeu cau dat xa hdi Do dd ddi mdi phUdng phip day hpe l i mpt viec lam can thilt va hit sUe quan trpng giai doan hien Ddi mdi phUdng phap day hpe chfnh la viee nham tfeh cUe hdi hdat dpng cua hpe sinh q u i trinh hpe tap d diy, giio vien can giup hpe sinh bilt tU minh kham p h i nhQng tri thQc mdi, qua dd eic em se thdng hieu, ghi nhd nhQng gi da ehii dpng ITnh hdi dQdc, tQ dd nim dQdc kien thUc mpt each sau sic hdn D^y hgc Phat hl^n va Giai quyet van de la phUdng phap day hpe tfeh cUc t h i hien dUde phan nao nhQng yeu eau neu tren Bii vilt chi xin dUdc neu mdt sd van de ve van dung Day hpc PH&GQVD viec hinh Phep nhan sd thap phan Idp Mat sa'va'n ae ve PPDHPH&GQVD a The nao la PH&GQVD? Cic phUdng phip day hpe truyen thd'ng trUde day, day hpe sinh hinh cac khii niem mdi, giio vien thUdng chii yeu hudng dan hpc sinh cich giai cic bii toin vf du (dUde coi la cie bai mau) ed sich giio khoa tren cd sd dd dUa nhOhg edng thQc, nhQng khii niem, ghi nhd dupe in sich va yeu eau eic em i p dung cic edng thQc, ghi nhd dd vio giai bii tap thuc hanh Viee lam ed thi ndi da khong phat huy dupe tfnh tfeh cUe hpc tap ciia hpc sinh bdi cic em hoan toan thu ddng tilp thu bai giang ciia giio vien mpt cich miy mdc ma khdng hilu dUde gdc r l eiia van de Neu nhQng van de dUde neu sich giio khoa dupe giio vien hudng dan hpc sinh suy nghT va tim cich giai quyet van de bang nhQng vdn tri thi/c ciia b i n than se giup e i c em phit triln tu mdt cich cd hidu qui Rd rang cic em se rit hUng thu dUde tU tim hilu van de va bing kha nang eiia minh dUa hUdng giai quyet van de Cd the se la rat khd khan, ddi ed the dan den that bai vl khdng tim dUde hUdng giai quyet nhUng doi lai, cie em se phit huy dUde tdi da tinh tich cue ciia minh bing cich huy ddng vdn tri thQc sin cd van dung vao viec giai quye't van de Khi cic em giai quyet dUde van de se giup eic em hinh va phit trien dUde nang lUc giai quylt van de cac tinh hud'ng tilp theo b Dac diem ciia Day hoc PH&GQVD Trong Day hpc PH&GQVD, giio vien la ngUdi td chUe dUa eae tinh hudng ed van de d l hpc sinh phat hien va tim each giai quylt cac van de NhQng van de ma hpe sinh can giai quyet la nhQng tri thQc mdi cd ndi dung bai vi vay khong phai bat cQ hpe sinh nao cung ed the giai quye't dUpe ma cic em thudng phai no luc van dung cac tri thQc vd'n cd dUdi sU hudng dan chi bao eiia giio vien Day hpe PH&GQVD ed nhQng dac dilm sau: " Hgc sinh tich ede, ehu ddng tim kien thdc mdi Vidu: Khi hpe ve phep nhan sd thap phan, hpe sinh se ehii dpng tim md'i quan he giQa sd thap phan va sd tU nhien qua viee ddi ddn vj d day hpe sinh da biet each vie't cac ddn vi dd dai dudi dang sd thap phan, tQ dd gap van de nhan sd thap phin vdi sd td hien hay sd thap phan can giai quyet, eae em se van dung de dUa cac sd ve dang sd tU nhien de nhan sau dd ddi ket qua ve dang sd thap phan *Hpc sinh dUde tang cUdng trao ddi, thao luan Vidu: Khi hpc ve phep nhan sdthap phan, hpc sinh se trao ddi eung de giai quye't van de m i giio vien dUa dd l i thuc hien phep nhan sd thap phan vdi sd tU nhien hay sd thap phan Hs se ban bac de tim each giai quyet van de * Khuyin khich hpe sinh tU hpc, tU khim phi Neu nhu day hpe theo kilu thuyet trinh gay trd ngai cho tiln trinh hpe tap mdt cich tich cue, chii dpng eiia hpe sinh thi day hpe PH&GQVD se khic phuc dUde tinh trang dd, hpe sinh se phai phat huy tinh tfeh eUc, chii dpng qua trinh hpe tap de tu minh tim nhufng kiln thQc mdi cho ban than TQ dd dan dan hinh d hpe sinh mdt nang luc tU hpe, tU kham phi, phit hien va giai quyet van de Vi du: Khi hpc xong ve phep nhan sd thap phan vdi sd tu 808-2011 DatjvaHoc nhien, HS cd t h i tu k h i m p h i v i p h i t hien c i c h nhan n h i m mdt sd thap phan vdi 10, 100, 1000 * Khuyen khfeh hpc sinh tU kiem tra d i n h g i i Dei mdi phUdng p h i p day hpc di ddi vdi viec k i l m tra d i n h g i i hpc sinh Viec k h u y i n khich, bdi dU6ng hpc sinh b i l t tU k i l m tra d i n h g i i q u i trinh hpe t i p Day hpe PH&GQVD se giiip hpc sinh b i l t minh can dUdc trang bj them nhQng k i l n thQc gl, tQ dd b i l t tQ dieu chinh q u i trinh hpc tap VI du: Khi hpc ve phep nhan sd thap phan vdi sd tQ nhien hay sd thap phan, hpc sinh phai b i l t dUde each doi e i c so dudi dang sd thap p h i n ve dang sd tU nhien de thUe hien phep nhan NhU vay giai q u i t van de hpe sinh bude phai van dung c i c h ddi ddn vj de thUe hien, tQ se giup e i c em biet dUPc can doi cac sd ve dang n i o cho phu hdp thuc hien c i e phep nhan dd * Day hpc PH&GQVD ed the i p dung cac giai doan k h i c Khi hinh k i l n thQc mdi, thuc h i n h ciing cd hay van dung k i l n thQc vQa hpe vao thUe t i l n , GV deu ed the dUa nhiJng van de yeu eau HS phai giai quyet Tuy theo ddi tUdng HS ma ed the dUa nhQng van de phu hdp d l cac em ed the tu giai q u y l t dupe Vidu: Khi hpc phep nhan sd thap phan vdi sd tU nhien hay sd thap phan, hs can phat hien v i giai quyet nhQng van de sau: - Khi hinh t h i n h k i l n thQc mdi: GV yeu cau hs tu p h i t hien c i c h thUe hien phep n h i n sd thap phan vdi sd tu nhien hay sd thap phan tren cd sd c i c h thUc hien phep nhan hai sd tU nhien - Khi thuc h i n h ciing ed k i l n thUe: Sau HS n i m dUde each nhan sdthap phan vdi s d t u nhien hay sdthap phan, g v e d t h i phat trien kT nang eho hs bang c i c h dUa phep nhan sd t i p phan cd sd chQ sd b phan thap phan khac - Khi van dung k i l n thQc vao thQc t l : Sau hpe xong ve phep n h i n sd thap phan, gv ed t h i cho hs van dung tfnh khdi IUdng, ehu vi, dien tfeh, ciia c i e vat cd thUc te hay giai mpt bai t o i n ed van dung c i c h nhan sd thap phan, e Cae budc trcng Day hpc PH&GQVD Day hpe PH&GQVD cd t h i chia t h i n h 4bUde sau: Bude 1: Phit hien vi tham nhap van de - G i i o vien neu van de, yeu eau hpc sinh p h i t hien van de can phai giai quye't TQ dd hpe sinh tham n h i p va tim h i l u van de Bude 2: Tim giii phip thde hien ^ TQvan de vQa p h i t hien ra, tren ed sdtim h i l u van de, hpc sinh cd the tU tim each giai quyet hoac dUdi sU hUdng dan ciia giio vien TQ mdt van de cd t h i cd nhieu c i c h giai q u y l t khac nhau, hQdng dan hpc sinh, giao vien can lUa chpn c i c h giai quyet eho phu hdp v i ed hieu qua nhat vdi ddi tUdng hpc sinh BUdc 3: Trinh bay giai phip - Sau da lUa chpn c i c h giai quyet v i tim tri thQc mdi, g i i o vieii tiep tue eho hpe sinh hinh t h i n h quy t i e , edng thQc, khii niem, bang c i c h p h i t bieu tren suy nghT eiia e i c em, tQ dd mdi rut cdng thQc, quy t i e , khai niem nhu S i c h g i i o khoa Budc 4: Nghien cdu sau giai phip Sau hinh dUdc e i c edng thQc, quy t i c , k h i i niem, g i i o vien can cho hpc sinh van dung v i o thUc hanh nham k i l m tra lai van de Khi van de dUde khang djnh c h i c c h i n dung, giao vien mdi cho hpe sinh dpc theo ndi dung s i c h g i i o khoa Van dgng Day hpc P H & G Q V D vigc hinh Phep nhan so thap p h i n b Idp Sau day xin dUdc trinh b i y cac bUcte cija Day hgc PH&GQVB viec hinh t h i n h ph6p n h i n mdt so t h i p p h i n vdi mdt s8 tu nhien v i c i c giai p h i p giup HS giai quyet van de ve thi^ hien phep n h i n dd: BUdc 1: Phat hi$n tham nhap van di - Gv neu vi du SGK, yeu eau HS tim ldi giai bai toin - Hs rut ra: , x = ? (m) va tim c i c h giiu quylt Budc 2: Tim giii phip thdc hien Giai phap 1: DUa ve phep nhan 2sc tU nhien - Gv gdi y hs doi c i c sd ve dang ddn vj dm - H s d o i : 1,2m = 12dm - Hs thUe hien phep n h i n : 12 x = 36 (dm) - Hs thuc hien ddi: 36dm = 3,6m - Hs neu k i t qua phep nhan: 1,2 x = 3,6 (m) - Cho hs so s i n h 2phep nhan: 12 x = 36 va phep nhan 1,2x3=3,6 • - Cho hs neu each dat tfnh va thUe hien phep n h i n mpt so thap phan vdi mdt sd tU nhi§n Giai phap 2: Dda ve nhan phan sd vdi sd tU nhien - Gv gdi y hs dUa 1,2m ve dang phan so 12 - Hs doi: 1,2m = — m 10 12 Hs thUe hien phep n h i n : — x : 36 Hs thUc hien ddi: — m = 3,6m 10 36 (m) 10 - C i e hoat ddng sau thUc hien nhU GiM phip Giai phip 3: DUa ve phep cdng c i e sd thap phan - Gv gdi y c h u y i n phep n h i n phep cdng - Hs c h u y i n : 1,2 x = 1,2 + 1,2 + 1,2 - Hs thuc hien phep cdng: 1,2 + 1,2 -H 1,2 = 3,6 (m) - C i c hoat ddng sau thUc hien nhU Giai phip BUde 3: Trinh bay giai phip Trong moi giai p h i p , sau HS dUa c i c h dat tfnh va thUc hien phep nhan mdt sd thap phan vdi mdt so tU nhien, GV cho HS p h i t b i l u bang Idi theo c i c h hieu e i nhan ve each nhan mdt so thap p h i n vdi mdt sd tU nhien, cho hs k h i c nhdn xet va bd sung trude rut quy t i e nhan ed SGK Budc 4: Nghien edu siu giai phip TQ quy t i e nhan HS vQa tim ra, GV can cho HS nghien cQu sau them bang c i c h dUa e i c vf dg ed sd c i c chQ sd phan thap phan k h i c d l van dgng quy t i c nhan Tren cd sd dd khang djnh tinh dung d i n eiia quy t i c va eho HS doc thudc ghi nhd SGK Tren day l i mdt sd van de ve van dung Day hpc PH&GQVD viec hinh t h i n h phep n h i n sd thap phan eho hs Idp Trong eupc sdng hang ngay, moi ngUdi ludn phai giai quylt cac van de sinh k h i c Viec day hpc t o i n khdng eh? l i day e i c tri thQc va kTnang t o i n hpe ma edn hinh v i p h i t trien b hpc sinh PhUdng p h i p hpc, nang lUc s i n g tao v i nang liic giai quyet van de Rat mong nhan dUde trao ddi ciia ban dpe Tai ll§u tham khao: Nguyen BaKim, Phdongphap day hpc mdn toan NXBDHSP, nam 2002 l.a.Leene (Phan Tat D i e djch), Day hoc niu vin dS, NXBGD, nam 1977 Duan phat trien giao vi&n Tieu hoc - Tai lieu BDGV - Dffimdi PPDHdTieu hgc- NXBGD 2005 ... 1,2 -H 1,2 = 3,6 (m) - C i c hoat ddng sau thUc hien nhU Giai phip BUde 3: Trinh bay giai phip Trong moi giai p h i p , sau HS dUa c i c h dat tfnh va thUc hien phep nhan mdt sd thap phan vdi... sd van de ve van dung Day hpc PH&GQVD viec hinh t h i n h phep n h i n sd thap phan eho hs Idp Trong eupc sdng hang ngay, moi ngUdi ludn phai giai quylt cac van de sinh k h i c Viec day hpc t... NXBGD, nam 1977 Duan phat trien giao vi&n Tieu hoc - Tai lieu BDGV - Dffimdi PPDHdTieu hgc- NXBGD 20 05