DAP.AN
Trang 2Vi6t phrtono uen
dtdrn I(-Z;p) ddn ti*p tuy6n td, tdn nh6t
Phrrong trinh ti6p tuy6n
@
u:6iTz@-uo)*ffi
Kho6ng c6ch tr) I d6n A : k : l?o + 2
DOI* Currh, t On* *6 , tr
.T)m duoc hai ti6p tuy6n y: x; y: *fi
9i6l ddi ph,ro"S triol, tn
e (7 - sinx)(6cosr + Zsinx _ Z) : 0
<+ sinx : t ho6c 6cosx *2sinx : 7 (VO
nghiQm )
GiAi vi k6t lu6,n nghiQm VUi
DK:x>0
B6t phrrong trinh tr6 thdnh y'T;E;:rtosrn
- < yEQos2r - s) DEt r : logzr b6t phuon*
(tr-zt-s>o
I
\t-3>o
It2-zt-s< b(t-s1z
-Gi6,i phxong trinh :
( )2*+82+6)0
I"'- t>o
<+ r ( -3 ho6c x ) tho6c r : _1
Trang 3N6u r ( -3 Thi VT > 0; Vp < 0 ft
o Khi x : -1 thi b6t phuong triuh th6a
o Vdi r > 1 thi b6t phuong trinh thh,nh :
e1/I{aT + {i *1: zJ;A1
Gi6i duoc : x : 1 ; * : _; ( loa, ).
KL : NghiQm phuong trinh : x: - 1; x:
Ti.nh gid td biiiu thrtc :A:4C?oo+_8Cf*;6
(1 +a)1m: Cloo +Clooa+Clsrxz + +Cltq.0-r00
(1 - r)rm : Cr* - Ci*r + C!**+ +Cffirroo
Suy ra: (1 + z)100 + (1 - r)100 : 2(Cf* + Cr2*r, +'"frffi
Dao hd,m hai v6 ta duoc :
t0O[(t + r)ee - (t - z)9e] ,: Z(ZC?* r: + 4Cf*r;s
+ + 1ggCfffzee)
Cho x - 1,ta drfgc,4 : l00.2ee
cho hinh chdp s.aBCD c6 sA = sB : gg : o1/2, ,d dd;y ABC rd to,rn gid,c cd,n , fu) : lzao, BC :2a T6nh thd ttch lchfi chap S.ABC
oHinh vE :
Trang 4Tinh duoc AB : AC : 4 \/5 '* ua S^* UABC =W =
3
vh b6n kinh dtrdng trdn ( ABC ) ld R: ,8.?.= :
Ha SHL(ABQSuy ru
SH:!/SF=V4:a'i6
Do d6 Vs.epc : *Sorr.sr :@ffi
T?.mI:l n-z u ,^
2 + !fili**
DAt t : \/iTI + n : tz,- tril :iat
,at ,: I;.ztdt:2^!- Adt
t + )dt : 2(; - t2 + t - 2tnlt + 2l) + c }ry t : 'tlill t, aoq k6t;;
Ttong m(.t phd,ng odi he
:::: A, qua A ad, cdt 1c;,tc,i rnu, ,;;;":;:;::";":r\l;:,
(C)c6 tam O(o;o
cria hai dudng trdn.
Phuong tr)nh drrdnr t
OH,OK vuOng g6c vdi A c6 AH : AK
+ oAz - oHz : AI2 - IK2<+ 5 _ Qr*r*_ g _ (za-zu)z
Gi6i dugc b: 0 ha,.y b t= _4a suy ra A: x_ 1 : g;l_ 4f1 T : o
2\/Ffi-rm
,m+;6
Ja2
4
:3b'
4
_ 3r,
4
va
,IF Va
,la
\,,1a
c2 +3
*-lo-
" 3
a2 +B
n*ro- > 3
MinP :io a:b: c : 1
N6u hoc sinh gi6i bing c6ch kh6c dr/a vAo thang diilm di5 cho.