Hl/dNG
D A N Q U A N L Y ,SlJf DUNG
TAO PHlAMi; HEN GlIlP HDC SINH PHAT HlEN, KHAM PHA TRI IHlK TIIONG
• • • • '
DAY tiOG mm Hf3E VMBm GIAN hEiP 11
• Biii V a n N a h i
Trudng Dai hgc SU pham Ha Ngi
Dgt van de Quan niem ve phUPng tien day hpc, ehung tdi thdng nhat vdi y kien ciia GS. TSKH Nguyen Ba Kim [2, trang 427]:
"khai niem phUPng tien dgy hpc dUdc hgn che d nhOng thift bj cd chOa dOng hoac chuyen tai nhOng thdng tin ve npi dung dgy hpc va ve sO dieu khien qua trinh dgy hpc", "ban, ghf... khdng phai la phOdng tien day hpc dung theo nghTa nay". Mdi phOPng tien dgy hpe ed the giup hpc sinh thOc hien mpt sd trong cac chOe nang sau:
k i f n tgo tri thOc, ren luyen kT nang, kieh thfch hOng thu hpe tap, td chOc dieu khien qua trinh hpc tap, hpp li hda cdng viee eua thay va trd.
Trong dgy hpe mdn Toan, khai thac tO ndi dung dgy hpe, giao vien da ed the gpi ddng ed, tgo hOng thO hpe tap cho hpc sinh, chang hgn, bang each lat ngOpe va'n de, khai quat hda, tOdng to hda...
Cung nho vgy, tO mdi bai toan, giao vien da ed nhieu cd hdi de khai thae, ren luyen cho hpe sinh each suy nghT, each g i i i q u y f t van de. Tuy nhien, nhOng each thOc dgy
hgc nghe ciJa hoc sinh.
Anh: Tuyet hAinh
hpe mdn toan nhO the phan nao cung lam cho mdn toan trd nen mdt mdn hpc "khd khan". Mdt li do khae nOa la cac phOPng tien dgy hpe dope sO dyng trong dgy hpc mdn toan eung cdn nhOng hgn c h f . Tham ehi, cd ngUdi cOc doan, cho r i n g trong dgy hpc mdn toan ehi can phan t r l n g b i n g den, khdng can gl nOa. T h i f t nghT, ne'u khai thae dUpe nhOng phOPng tien dgy hpe.
thoc hien dope mdt sd trong nhOng chOc nang dgy hpe nhO da ndi tren, se gdp phan thay ddi tinh hinh, lam cho mdn toan dd khd khan hdn. Nhieu thay cd giao dgy toan da lien he ndi dung toan hpc vdi thUe t f , mac dau cung chi la nhOng minh hpa eho bai hpc, song cung k h i f n hpe sinh thich thu hpe toan hdn.
Trong thdi gian gan day, da ed nhOng k f t qua nghien cOu ve sO dung phUdng tien trong dgy hpc mdn toan, chii y f u theo hUdng tang cUdng sO dung edng nghe thdng tin trong trinh ehieu bai giang, ve hinh, minh hpa... Trong bai bao nay ehung tdi de xua't mdt phUPng tien dgy hpc ddn g i l n nhUng kha hieu qua trong viec giup hpe sinh phat hien, kham pha tri thOe trong day hpe chOPng "dodng t h i n g , mat p h l n g va quan he song song"
[1 ], Hinh hpe khdng gian ldp 11 d trodng Trung hpe phd thdng.
2. PhUdng tign va khai thac phUdng tign dgy hpc
2.1. Phddng tien
PhOdng tien dgy hpe dope chung tdi trinh bay trong bai bao nay gdm mdt sd vat lieu
'immmm
nvii^'M^v.w So 49 thang 09 nam 2009 1 9HUfdNG DAN Q U A N LY, SC^ D U N G
quen thude va mdt phieu hpe tap. Cy the la:
- Mdt khay (K), dgng hinh hop chO nhat khdng n i p , dUde lam b i n g nhUa trong, dUng nudc trong, mau xanh, non nOa khay. Mdt mat ben (P) cija K ed ke hai dUdng t h i n g mau dd n i m ngang, song song vdi nhau, gdm egnh day a va dudng trung binh b, mat ben (Q) ddi dien vdi (P) eung ed ke hai dUdng t h i n g tUdng to, gdm egnh day c, dodng trung binh d va cham mdt diem A gan tam cua ( 0 ) lech len phfa tren mdt chut.
- Mpt m i f n g bia eOng (B), ed nhd (cd the dat lot vao trong khay K), cd the tha'y rd ngan node khi dat B vao trong node d khay K, ed mdt mep t h i n g va ke nhOng ddng song song vdi mep dd (de tien quan sat cae dodng t h i n g song song),
- Mdt thode ke ed chia mm va mdt thude ke det,
- Mdt p h i f u hpe tap, ghi nhOng hUdng d i n hogt dpng va bang ghi ket lugn, tUPng Ong vdi ndi dung hoat ddng.
2.2. Cic hogt dgng
Ta ed the hudng d i n hpc sinh dung nhOng dyng cy hpe tap ndi tren de kham pha, phat hien nhOng tinh cha't ve quan he song song b i n g each thOe hien nhOng hogt ddng dodi day. Sau mdi hogt ddng, ghi Igi k f t qua tren phif'u hpe tap.
Bii 1. Hai dUdng thing song song
Hogt dgng 1. Djnh li ve ba giao t u y f n .
Ta eoi mat day (D) va mdt mat ben (P) eua K la hai mat mat phang, mat nUde la mat phang thO ba (a). Ba mat phang nay e l t nhau tOng ddi.
theo ba giao t u y f n . TO tO nghieng di nghieng Igi khay K de vj tri ciia ba mat phang nay thay ddi. Trong mdi trOdng hpp, khi mat node da dOng im, hay xae djnh cae giao tuyen cua ba mat phang nay va neu nhan xet ve vj tri tUPng dd'i eua ba giao tuye'n dd. Ghi k f t q u i vao p h i f u hpe tap.
Hogt dgng 2. He qua Mdt mat ben eua khay K dupe eoi la mdt mat phang (Q) di qua mdt egnh day c, mat nUde dupe eoi la mdt mat phang (a). Thay ddi dp nghieng eua khay K sao cho mat nUde ludn di qua dOdng t h i n g b eua mat ben (P), dd'i dien vdi (Q).
Trong mdi trOdng hpp, khi mat node da dOng im, hay quan sat giao t u y f n eua hai mat phang (0) va (a) va phat hien xem vj tri tOPng ddi ciia giao tuye'n nay vdi b, c nho the nao? Ghi k f t qua vao phifu hpe tap.
Hogt dgng 3. Tinh chat bae eau.
Tren mat ben (P) cua khay K cd egnh day a song song vdi dodng t h i n g e, tren mat day cd hai egnh day a, b song song vdi nhau. Cd tfie ndi gl ve vj tri tOdng dd'i eua b va c ? Ghi ke't qua vao p h i f u hpe tap.
Bii 2. Dudng thing vi mgt phing song song
Hogt dgng 4. Nhan biet dudng t h i n g song song vdi mat phang.
TUPng to ap dung 2, thay ddi dd nghieng eua khay K sao eho mat nUde (a) ludn di qua dudng t h i n g b eua (P).
Cd the ndi gl ve vj tritUdng dd'i eua dudng t h i n g d cua (Q) vdi mat nude (a)? Ghi k f t qua vao phie'u hpe tap.
Hogt ddng 5. Tinh chat cua dudng t h i n g song song vdi mat phang.
TUdng to ap dyng 4, thay ddi dp nghieng eua khay K sao cho mat node (a) ludn di qua dudng t h i n g d eua (Q).
Phat hien vj tritUdng ddi eua d vdi giao t u y f n eua hai mat phang (P) va (a)?Ghi k f t qua vao phie'u hpc tap.
Hogt dgng 6. He q u i Thay ddi dd nghieng eua khay K sao eho mat nUde (a) song song vdi d. Lgi ed mat phang (P) cung song vdi d. Cd the ndi gl ve vj tri tUdng dd'i cua d va giao t u y f n eua hai mat phang (a), (P)? Ghi k f t qua vao p h i f u hpe tap.
Bii 3. Hai mgt phang song song
Hogt dgng 7. Tdn tai hai mat phang song song
Dat khay K nam ngang tren mat ban de mat nUde song song vdi mat day (D) eua K va dd them nUde vao K de thay ddi vj tri eua mat nUde (a). Cd the tao ra mat phang (a) di qua diem A cho trUde (cha'm t r f n mat phang (0)) sao cho mat phang (a) song vdi mat phlng (D) dupe hay khdng va tgo dupe bao nhieu mat phang (a) nhu the'? Ghi k f t qua vao phieu hpe tap.
Hogt dgng 8. Tfnh chat eua hai mat phang song song
Thay ddi vi tri cua khay K, neu tinh chat ve hai giao tuyfn cua mat p h l n g (a) vdi cac mat phang song song (P), (Q). Ghi k f t qua vao phie'u hpc tap.
Hoac la, dat khay K n i m ngang tren mat ban de mat nude song song vdi mat day (D) eua K va dd them nUde vao K de thay ddi vj trf eua mat nUde (a). Neu tfnh chat ve hai giao tuyen eua mat phang (P) vdi hai mat phang (a) va (D).
20
Sd 49 thang 09 nam 2009 £2**i i Mimm m
HSB'tf^Etlira F r i A f n r i P '
sOf DUNG
Hoac la, dgt khay K n i m ngang tren mat ban de mat nude song song vdi mat day (D) eua K. DOng mdt m i f n g bla eOng (B) ed mdt mep dope e l t t h i n g , dat Ipt dope vao khay K sao eho mep t h i n g eua bia n i m sat day eua K.
Nhan xet ve hai giao t u y f n eua mat p h l n g (B) vdi mat day (D) va mat nUdc (a).
Hogt dgng 9. He qua Dat khay K n i m ngang tren mat ban de mat nUde song song vdi mat day (D) cua K.
Dung mdt m i f n g bla eOng (B) ed hai mep la hai dodng t h i n g song song, ed chia ddn vi dai (mm), mdt mep dope cat t h i n g , xien gdc vdi hai mep song song, dat Ipt dope vao khay K, sao eho mep t h i n g cua bia n i m sat day ciia K.
Nhgn xet v f dp dai hai dogn tren mep bia B, bj c h i n bdi mat day (D) va mat node (a).Ghi
k f t qua vao phifu hpe tap.
Hogt dgng 10. Djnh liTa-let trong khdng gian
Dgt khay K n i m ngang tren mat ban va lay c h i f e thode ke det (R) dat tren mat khay K (khdng chie'm h f t mat khay K), ta dope ba mat p h l n g song song la (R), (a) va (D).
DOng mdt thUde ke (T) cd chia ddn vj dai (mm) dat vao khay K sao eho mep ed chia ddn vj dai cua T tOa vao (R) va sat vao day (D) eua K. Vdi mdi vj trf eiia T, ghi Igi sd do hai dogn t h i n g eua T do ba mat p h l n g
ndi tren chia ra. TO bang k f t q u i , hay nhgn xet v f tl le cua hai dogn t h i n g dd. Ghi ket q u i vao p h i f u hpe tap.
2.3. Phieu ghi cic ket qua hogt dgng:
(trong p h i f u hpc tap, cdt ghi ket qua dUdi day de trd'ng, cho hpe sinh ghi)
2.4. Td chub hogt dgng tren Idp
Noi dung
1. Neu ba mat phing ciit nliau theo ba giao tuye'n phan biet thi ba giao tuyen ay...
2. Neu hai mat phdng phan biet lan li/dt chifa hai dudng thdng song thi giao tuyen cua chung (neu c6)....
3. Hai dtrbng thing phan biet cClng song song vdi dUdng thing thiJbathi...
4. Ne'u dudng thing d khong n^m trong mat phing (fl^ ) va d song song vdi dudng thing b nim trong {Ot ) thi...
5. Cho dudng thing d song song vdi mat phing (P). Neu cd mat phing {O ) chita d va cit (P) thi giao tuyen cua (P) va {OC ) se...
6. Hai mat phing cit nhau, cUng song song vdi mot dUdng thing d thi giao tuyen cua chung...
7. Qua mot diem nim ngoai mot mat phing cho trudc cd bao nhieu mat phing song song vdi mat phing cho trUdc dd?
8. Mpt mat phing cit hai mat phing song song cho trUdc thi hai giao tuye'n se...
9. Hai doan thing song song bi chin bdi hai mat phing song song thi...
10. Ba mit phing song song dinh ra tren hai cdt tuyen nhu'ng doan thing...
Ket qua dong quy hoac doi mot song song vdi nhau
song song vdi hai dUdng thing dd hoac trUng vdi mot trong hai dUdng thing dd song song vdi nhau d song song vdi (pt ).
song song vdi d.
song song vdi d.
cd mot va chi mot mat phing.
song song vdi nhau.
bing nhau tile
NhU da ehi ra d tren, trong moi bai, giao vien cd the chia s d hpc sinh eua ldp thanh tOng nhdm hogt ddng, vdi ba hoac bdn hogt dpng, trong khoang thdi gian 20 phut. Sau dd eac nhdm thdng bao k f t qua hoat ddng cho e l ldp b i f t , thdng qua phie'u hpe tap. T i f p dd la cae hogt ddng chOng minh va van dyng.
Cung cd the sO dung cac phan mem ve hinh, sO dyng tinh dpng de md phdng eac hogt ddng ap dung d tren, chang hgn: phan mem Geometry Sketchpad, Cabri 3D...
KET LUAN
PhUdng tien dgy hpc, nhU chung tdi da de xua't d tren, cd the tgo nen hang chye pha dgy hpc ve quan he song song trong khdng gian, lam cho hpc sinh hpc tap hOng thu hdn, tich eOc, chu ddng hdn trong viee kham pha, tim ra nhOng tri thOc mdi, gdp phan ddi mdi phOPng phap day hpc m d n toan d ta/dng pho thdng."
TAI LIEU THAM KHAO LTran V5n Hao (Tdng chu bien) Nguyen Mong Hy (Chu bien) - Phan VSn Vien - Khu Quo'c Anh - Nguyin Ha Thanh. Hinh hgc 10 - Hinh hpc 11. NXB Giao dgc, 2007,
2. Nguyin Ba Kim.
PhUdng phap dgy hpc.
m6n Toan. NXB Dgi hpc Su phgm, 2004.
3. Dao Tam. Phuong phap dgy hpc Hinh hpc 6 trudng Trung hpc Pho thong. NXB Dgi hpc SU phgm, 2007.
So 49 thang 09 nam 2009 2 1
