REN LUYEN Kl NANG THITG HANH CHO HOC SINH T H O N G QUA
DAY HOC "BAI TAP VA THl/C HANH 1 " (TIN HOC 11)
O TS. TRAN D O A N VINH*
T
rong chuong h-inh Tin hpc 11 d THPT, hpc sinh (HS) b^l ddu CIUTC ldm quen vdt ng6n ngO l^p Irtnh Pascal. Ddy Id mdl ngdn ngd l^p Irlnh bdc coo vd HS lhu6ng g<^p rdt nhldu khd khdn Irong qud trinh tt^ ihu 1(1^ thCrc. Ngodi vl$c ndm vOng cdc kl^n thuc It thuyllt, HS cdn phdt hodn thdnh mdt sd bdi Idp thi/c hdnh. Mvc dIch oia cdc bdi hpc Bdl t^p vd ihi/e hdnh Irong chuong Irlnh mdn Tin hgc Idp 11 td nhdm gtOp HS cOng cd k i ^ ihuc, r6n luy^ klndng ihvc hdnh qua v i ^ gidl mdl sdf bdi bdi tdp tin hpc,... Bdi vilt ndy di cdp vdn d4 rin luyjn Iff nfing thi/c hanh tin hpc cho HS thdng qua dgy hpc bdl: «Bdl t^p wJ tfure ftdn/i r (Tin hpc 11, Ir. 34).1. Mvc dIch vd ydu cdu
Bdf t^p vd thi/e hdnh I Id bdi tdp ihi/c hdnh ddu Hfin Irong chuong Irlnh Tin hpc 11, nd cd ^ nghTo rdt quan trpng ddl v6l HS. VI thi, GV cdn quon tdm din nhOng kiln thuc Idn kr ndng, kr xdo md HS phdi dpi dupe Irong qud Irlnh dpy hpc. h<lhang mvc dfch, yfiu cdu md HS cdn dpi dupe trong dpy hpc bdl hpc ndy, dd Id: • Bilt vill mdl chuong trinh Pascal hodn chinh don gidn;
- Bill 5i> dyng mdl sd djch vy co bdn cuo Turbo Poscol Irong sopn thdo, luu trO, djch vd thyc hlf n chuong Irlnh.
2. Ndl dung dpy hpc bdl: «Bdl tdp vd thi/c hdnh 1 '
Bdl: <rBd/ tdp vd thi/c hdnh I' cd ndl dung chinh nhu sou:
al Gd chuong Irlnh sou:
program Giai_PTB2i
xl, x2: real;
begin clracr;
writeCa, D, CS '
readlnia, D, c) j D!=b*b-4*a-c ;
xl;-(-b-aqrt(Df)/(2'a);
x2:.-b/a-xl..
writ«{'xl-',xl;6:2,•x2=',x2!6:2)j end.
Aid' sddlim cdn luu ^: - Ddu chdm phdy (;) dOng dl ngdn cdch cdc khoi bdo vd cdc cdu l^nh;
- Sau 10 khda end cudi chuong trinh phdi ddl ddu chdm (.).
b) Nhdn phim F2 vd luu chuong Irlnh vdi tin PTB2.PAS lln dfo.
c) Nhdn Id hpp phIm Alt+F9 d l djch vd siio Idi cu phdp (nlu cd).
dj Nhdn id hpp phim QH+F9 d l thyc hl^
chuong Irinh. Nhdp cdc gid lr| 1; -3 vd 2. Quon sdt kitqud hiln thi tr«n mdn hinh (xl - 1 . 0 0 x 2 - 2.00).
e) Nhdn id hpp phim OH+F9 rdl nhdp cdc gid lr| 1; 0; -2. Quon sdt kit qud hlln lh| Irfin mdn hinh ( x l . •1.41x2.1.41).
f} Sdo Ipl chucmg trinh Irin soo cho khdng dOng blln Irung glan D. Thvc hl|n chuong Irlnh da sOo vdi cdc bd do ll|u ti«n.
gl Si}a Ipl chuong trinh nh^n dupe d cdu c) bdng cdch thay ddl cdng thuc Knh x2 (cd hot cdch dlHnhx2).
hJ Thvc hl|n chuong Irlnh dd sua vdi bd du ll|u 1; -5; d. Quan sdt kll qud Irfin mdn hinh ( x l - 2 . 0 0 x 2 - 3 . 0 0 ) .
tj Thi/c hi|n chuong Irlnh vdi bd dO ll|u 1; 1; 1 vd quan sdl kll qud Irfin mdn hinh.
3. Cdch ihiic llln hdnh
Ddy Id bdl Idp vd Ihvc hdnh ddu Hfin nfin GV cdn ed $v glup dd ddl vdt HS Hong cdc thao Idc,
•Tn«i|l|ittcs«(tyiUN«i
Tap chi Blao due s6 2 9 1 (M i • »/aoi«i
chdng hpn nhu: khdi ddng mdy llnh, kfch hopt phdn mim Turbo Pascal (nhdp chudt Ifin bilu tupng Pasco! Irfin mdn hinh nin Desktop hodc ISn ifip Turbo.exe trong ihumveTPcdothumvcBIN 4 1 dto C hodc d dia D). Tllp d i n , G V y l u cdu HS thvc hlln Iheo thii tv cdc edu hdj trong bdl tap nhu sou:
a) Go chuong h-lnh do cho gidng nhu sopn thdo vfin bdn h-ong mdn hinh Idm vi|c cda Pascal.
6 hoot ddng ndy, G V luu y vdi HS nfin gd bdng dild$Hlng Anh, chOvlltthudng vd In ddm nhOng tfin ddnh rifing trong chuong h-lnh nhu program, uses, var, begin, end;
bl luu chuong trinh vdo dio vdi t i n Id PTB2.PAS bdng cdc
thao tdc sou: Nhd'p chudt Ifin mvc File ho<ic nhdn phim F2 {hinh I);
hdp ihopi Save File As xud't hifin. Xi> li hdp thogi: + G d l l n l | p PIB2vdomvcSovBAfe as; + Gd phim Enter hodc nhdn phim OK.
ddng thdi td hpp phim C H + F 9 . Khi dd, Irfin mdn hinh xud't hi|n ihdng bdo nhdp vdo ede gid hj a, b, c. Sou khi nhdp xong cdc gid trj: o - l , 6 - -3, c - 2 l h l kit qud Clio chuong h-lnh Id x l - 1.00x2 -2.00ihlnh3).
d hogt ddng ndy, G V cdn nfiu mdt sd' luu y cho HS, dd Id: - Khi nhdp ede gid Irj a, b, c to nfin gd ddu edeh sou mdl Idn nhdp mdt gid trj; - D l quay trd loi mdn hinh sogn thdo chuong Irtnh, la gd phIm Enter. Mud'n nhdp vdo cdc gid trj khdc cuo a, b, c, to phdi chgy Ipl chuong Irtnh.
el Di thvc hi|n chuong Mnh vdi bd da li|u a - 1 , b - 0 vd c - - 2 ihl kit qud h-fin mdn hinh s8 I d x l - 1 . 4 1 x 2 . 1 . 4 1 ( / i ) n / i 4 ) .
Changs d i p . . . Print Ppintar s e t u p . . . DOS >l>nU
Exit Alt.X Hlnhl.Ch<!nFlle/F2 :l Djch vd sOa ISi cO phdp (nlu cd): 0 hopt ddng ndy, G V cdn glup IOng HS djch vd sOa Idi dwang h-lnh Hfin mdy Knh. D l djch chuong Irinh, to nhdn ddng thdt td hpp phfm All+F9. Khi djch diuong hinh, nlu thdy cd ihdng bdo Idi, G V ed ihl gidl thidu cho HS xem p/iv V c 7: Mdl sd ihdng bdo ISi d cudi SGK.
Sou khi djch xong chuong H n h , hfin mdn hinh xudthl|n thdng bdo: Compile succeshjl: Press any key (da dich thdnh cdng: hfiy go mdt phim bdt kl)dltilptvc^/>ln/i2J.
Hinh 2. DIch xong chuong Irtnh d) Di • • » i ^ l : I L H ^ I I . J i U I ^ tnifc hi$n
chuong Wnh, GV hi;6ng
dSn HS nh^n Hinh 3. Kit qud cOa chuong hinh
ftp Chi Glao due so 2 9 1 (idi-i/aoia)
Hinh 4
f} GV hir6ng dSn HS 5i>a Igl chiremg h-lnh h-Sn khi khdng dOng bi^n hung glan D b^ng cdch gdn x l : = ( - b - a q r t ( b * b - 4 « a * c ) ) / ( 2 ' a ) ; x 2 ! = - b / a - x l ;
Khi 66, chuong h'lnh duoc hi^u chTnh Iql nhu sou:
p r o g r a m Giai_PTB2;
x l , x2 : r e a l ; b e g i n
c l r s c r ;
write('a, b, cr ' ); readlnia, D, C )
xl!=(-b-Bqrt(b«b-4'a-c))/(2*a);
x2:=-b/a-xl;
writel'xl=',xl:6!2,'x2=',x2:6:2);
readln;
e n d .
Do d6, khi nh$p cdc b$ dCr li$u 1 ; - 3 ; 2 vd 1;
0; -2 th} Vit qud cOa chuong trtnh khdng cd gl thoy dj$l so v6i khi dung biln trung gian D {xl=
h00x2''2.00y6xl=-l41x2'1.41).
g) Si}a Igi chuong trinh d l Knh nghiem x 2 theo hal cdch sou:
Cdch J:Thayc6ngthu'cx2:=-b/a-xlb^ng c6ngthl>c: x2:-(-b+sqrt(b*b-4*a*c) )/(2*a};
Khi d6, chuong trinh s3 Id:
Progran Glal_PTB2;
UB«« c r t ; V«E
a, b, c: r e a l ) x l , x2: r e a l ; B«gln
c l r s c r J
vnriteCa, b, c: ') ; readln{a, b, c ) ;
xl:-{-b-sqrt(b*b-4•a*c)}/(2*a)(
x2:-{-b+aqrt{b'b-4*a*c))/(2*a);
write('Xl-',xl:6:2,'X2-',X2:6:2),•
readln;
End.
Cdc/t 2: Dung bftfn phi^ D vd ihoy cdng lhi>c x2: —b/a-xi b6ng cdng thiic: x2: - (-b+aqrt (D)) /
(2*a). Khi dd, chuong trinh sS Id:
progran Glai_PTB2;
us«a c r t ;
var a, D, c, D: r e a l ; x l , x2: r e a l ; b ^ i n
c l r s c r ;
w r i t e { ' a , o, c; ' ) ; readln(a, D, C) ; D:=b*b-4*a*C;
x l : - ( - b - s q r t ( D ) ) / { 2 * a ) ; x2:-(-b+sqrt(D))/(2*a);
write{'Xl-',X1:6:2,'X2=',X2:6:2);
readln ;
•nd.
h) V6I b$ do li$u 1; -5; 6, chirong Wnh dd sua trdn y g) s3 cho to k^t qud trdn mdn h)nh Id [xl' 2x2'3i {hinh 5\:
D \TP\BIN\TURBO EXE
trinh cho ta k^t qud Id m$t thdng bdo I5l: Error 207; Invalid floating point operation, nghta Id phdp todn v6l di6u phdy d^ng khdng hgp 1^
{blnh 6).
/; V6I b§ da li$u 1; 1; 1 thJ khi dfch chuong
Hinh 6. Thdng bdo ISl 207.
Oi r6n luy$n kr ndng thi/c hdnh tin hgc ndl chung vd lOT ndng l$p trinh trdn ngdn ngCt Pascal ndl rldng, GV cdn r ^ HS kr ndng ty khdl d$ng mdy tfnh, Vidti hoot phdn mim Turbo Pascal vd nh^p chuong trinh, [3 ndng d j ^ chuong trinh, \3 nfing sOci chuong trinh, kr nfing thyc hidn chuong trinh. Id nfing luu chuong Irlnh,... Tlidng qua tOng kr nfing nhu vfiy, HS sS hinh thdnh vd tv rdn luydn Id ndng thyc hdnh tin hgc m$t cdch t^t nhdt. Ben cgnh dd, GV cdn c6 cdc hogt d^ng dgy hgc ihich h?p nhdm glup dd, d$ng vidn HS c6 ni4m tin, y' thuc kl lu$t, tv gidc vd say md trong hgc tdp. Chl khi dd, gid hgc bdi t$p vd thvc hdnh mdl dgl hi$u qud coo. •
# .
T M I l ^ u t h a m k h i o
1.1. F. Kharlamov. Ph^t huy tfnh tkh cvc bpc tfp cda bQC sinh nhirtbtfnAo. NXB Gido (/(ic, H. 1978.
2. Hd SI D&m (cliO bien). Tin h^c 11. NXB Gido dvc H.2006.
3. Tr&n Do&n Vinti (cM bifin). HQC ttft tin h^c 11.
NXB Dgi hpc quic gia TP Hd Chl Minh, 2007.
SUMMARY
for practiced Mil training for students beSeve we need to trc^ tttelr own skBIs to boot the computer, software activation and enter the Turtio Pascal program, service program sklSs. repair sfcAb program, practical sidlls program, save the program skSls...
Through every student skills as tralnhg wlH tonn and Informatton tectw^ogysktOs practice formyselfin ttie best way. From this, teachers need appropriate activities to help and encourage them to have confidence, sense ofc^sr^p^e. self-dlsc^ln&, Ngh self and passion In learning. Only ttien school a^nm^ts and newpractk::es are t)lgNy effective.
Tap chi filao due s6 2 9 1 iki i • a/aoni