PHAT HIEN TJNH CHAT HAM SO MU LOGARIT Diriil s u HO TRO COA PHAN M E M THE GEOMETER''''S SKETCHPAD ThS BUI THI DIEM TRANG" 1 Cae phuong phap day hpc (PPDH )tich cue l iy hpc sinh (HS) lam tmng tam tiiudn[.]
PHAT HIEN TJNH CHAT HAM SO MU - LOGARIT Diriil su HO TRO COA PHAN MEM THE GEOMETER'S SKETCHPAD ThS BUI THI DIEM T R A N G " Cae phuong phap day hpc (PPDH )tich cue liy hpc sinh (HS) lam tmng tam tiiudng mat kha nhieu ttid^ gian, eang khd khan hon nhflng ndi dung giam tai (ehitiifla nhan, khdng chflng minh) ma v i n ddi hoi ngudi hpc ti;phat hien kien Uiflc mdi, hieu ttiau dao, toan dien van de Khi sfl dyng cae san pham cdng nqhetiidng tin nhula mdt phupng tien day hpc, ta cdttie khai tiiac nhflng die'm manh cua ndnhutinh minh hpa, tiyc quan, tinh kiem chflng, nham giiip HS ren luyen, phat trie'n tfl toan hpc, n i n g luc kham pha, phat hien va giaiquyetvan de DcS vdi phan mem The Geometer's Sketchpad (GSP), viec thiet keti^t day giup ngudi hpe phat hien tinh chait ham so mu - logarit d i e biet phfl hc^ vi nd cd the khic phyc cac nhupc diem neuti^en,hPn nfla, viee soan giao an dienti}dnpidungnaybingphan mem GSP dac biet nhanh ehdng vadPn gian trald^;-Budc4)HS phathien dupc tinhchat cua ham sdmaGV can tiuyen dat 2.3 Cae y tudng eu tiie giup HS phat hien tinh chat ham sdm u >' = a ' va ham sd logarit y = iQg„ ^ 'Hamsdmu-V = o': GV gidi thieu dang thi v i ten cua chung (hinh 1) Sif dung PPDH tich cue giup HS phat hien tinh chat cua ham sd'mu - logarit dudi s i ; hd tra phan mem GSP 2.1 Day hpc tieh cue l i PPDH dupe su dyng quatrinh day hpc n h i m phat huy cao nhi't tinh tieh cue, ehu ddng, ddc l i p , sang tao cua ngfldi hpc dflcrt vai trd td'ehflc, dieu khien cua giao vien (GV) Cd nhieu PPDH tieh cue rihu: phuong phap vi'n dap, phat hien va giai quyetvan de, hoat ddng nhdm, ddng vai, MdiphuPnp phap deucduu tSem eua nd, quan trpng la ngudi thay lua chpn cho mlnh mptcach rieng phfl hpp vdi myc tieu, ban c h i t cua vi'n de can tiao da Trong npidung kien ttiuc nay, chflng tdi ehpn phupng phap vi'n dap, vdi sudan xen gifla vi'n dap minhhpavatimtdi ^ b e x u a t y h ; d n g s d d y n g phan mem GSP va hettiong eau hoigiup HS phathien tinh chit h i m so mu - logarit Cac budc giflp HS phat hien tinh chit mdt ham sd dudi sfl hd trp cua phan mem GSP: - Bude 1) G V gid^ thieu thi va ten cua thj bang phan mem GSP;-Budc2)TUPng tae vd^ phan mem GSP b i n g each tiiay d a lientiJCcac giati'j tiiam sdde HS quan sat va tim nhflng tinli chi'ldae trung, khdng dd1 cua thj; - Bude 3) GV d i t eau hoi gpi y de HS (ki 2-8/2015) Thay ddi cae giati-jeP sd, v i n gifl a > [hinh 2) * TnfOnsTfing dgc ttiongThot Not, P Can T1i0 Tap chi Gido dye so 364 31 GV lan li/ot (Jat cac cau hoi: Ti) ijo thj, em hay cho biet: + Vj tri cua thj? TiJ suy tap xac djnh, tap gia trj cua ham so?; + Si/bien thien? (Neu cac Ithoang dong bien, nghjch bien cua ham so); + Ham so CO tiem can I1) GV tiep tuc cho thay doi gia trj co so (trong viing 0