! !"#$%#&'( "#$( 4 điểm ) !)*+,-#$*./01 #2#$3456"#'7 l 1-)8*9)1:;"#$3456<9=4#1* =#>9?1@'0A? 5B9'$##C9#+9?1$ (DE#1F#'G1*#CHI'9#: (J1*.1*K#CH7?9#:8 "# ( 4 điểm) L?#BH 9;#$3456 M MM156#49='-*NO?!2 P#$1*#Q3M%R#'7S) M%#8TH 156#1+!)*+U!B,J9V(80 1@'NO?37WR S9?5!B9H91 1Q)J*9)1:#$34569=9# V uur M"%I(7X#A?!Y##CNO?1Z9?9 ([3?. ZO#9=53G\#9)1:9? 9[94##C 34&#CH3 !3;5 (]'3H9!3;5"[#'7#S#1:9#S#G'#CNO?!?^'E!JH9$ !)#'G1* "#%8( 4 điểm ) _1+*1HEO?#'`1F9?1@'1?::#1H5J9V80Z (L H π = Ra9L #$G1`156#8 (bc#41FE!FLML 91`a"#$#E#3Z ^'.I' d]4#e#CA3Z/'-/ dfaMa MΩJu AB 9#51*7N1H i!?:##[#g8[L 9OE#1FI4#e#C#E#A3Z# (JE!F#CL.?.1G31'#eaR1HEQ#=u AB h1@':#1H'H# 9=#51*7N1H!?:##[ "#&8( 4 điểm ) *4J!Y"#E#H"Hh"#'#?i156#1+U1Q8 !?4#$*#*'j&#'#?8k5=#*'j&#$#Qn?3[[ 5h1B')l"#'#?"hH1* J9V(8_I'23[^'Gm T85!'H#?3[I?#?#*'j&#'G1*!2#9 #'4#g#.??!3;480;^'IEc'j&949 OAIS!?1`Hc3[9'j&31E3G8 (nH1*?J'j&>1@'!?!3;4o[H561W #'#2#?3[1Z# (TW#?ZISZ)H1*#C343[!?^'E!JC& !!3;4 / 0 p b V uur / 0 A 1 A 2 A i "#'8( 4 điểm ) *2'3[Uq#@'156#-C#$#ZI'2 M"%9156#1+OAc*1GIE]9*#>IE 5J9V8 (01@'5J156#3?.#E#;2c]9. #C$^'2'3[r#8[E3[#?#C+#@' (bc#41F]"J156#*9F![#C2'3[I?#?3 1`3?.#E#c2'3[9J#gIE\]I' 3^'2'3[#?9HIE!N#$153[31`k M s#8DE#1F9F![2'3[# #(bc#41F]9h3?.#E#iM%t#"! FZ2' 3[A?5BI?I?9=!Y##[#C$J#$*9F![#C2'3[153[#C9HIE !N!)#$3[#5=#;28DE#1FE!F;299F![2'3[31$ ] i !Y##[f ()*+,-, ./ 012 ! "#$(4 điểm) L&' *7' "%1 bXp!'1G#CRbR b @569F![994##C34 &#CHI'9#:8 F![#Cb156#OE#1Fh ( ) .2 /3 2 2 /3 5 l m OG l m m = = + "%1 A?1F'.??1*56#$ 0 2 2 3 3 G mV m m V = + ÷ uur uur 0 2 5 G V V⇒ = uur uur ( "%1 "%1 ?A^'E[149=34&#CH ( ) 2 2 2 2 1 2 2 3 11 2 12 5 3 5 15 l m I m l m l ml = + + = ÷ ÷ "%1 A?1F'.???A1*56#$ 2 2 0 2 3 11 3 5 3 / 5 15 m V l ml l = ÷ "%1 0 6 . 11 V l ω ⇒ = ( "%1 I'9#:34&#CH#'G1*FZ9=94# G V uur 156#OE#1Fh(9?*H^'!?+U^' b9=4#1*$#156#OE#1Fh( "%1 L&' *7' "%1 *K#CH!5=#9#: 2 2 1 0 0 1 2 2 3 3 m m E V V = = ÷ "%1 *K#CHI'9#: 2 2 2 1 2 1 2 3 2 G m E m V I ω = + + ÷ "%1 T 2 2 0 8 33 E mV = "%1 *.#C1*K#CH!?^'E!J9#: 2 1 2 0 1 11 E E E mV∆ = − = "%1 / 0 p b "#$(4 điểm) L&' *7' "1 fG\#9#:" ZO#9=5!?I'4NO?Fu !?I'4H9 d(7?1*1'N9=#'3J π + = m m T k "%1 "%1 "%1 3?.#@J " π + ∆ = = ≈ m mT t s k "%1 4##CH d(I'9#:156#OE#1Fh 0 0 0 0 3 2 2 3 m m V V v v = ⇒ = "%1 f9 >1@'!3;5"A?1F'.??K56 J4#1*#CH d(#v 0 v 8 4##C34&#CH156#OE#1Fh ( ) ( ) 1 2 1 0 / 2 / 2 G m m m V m m v + + = + 0 0,3 / 5 G V V m s⇒ = = "%1 "%1 "%1 L&' *7' "1 b>H^'#Z'9?34&#CH"!?H^'#Z'#$ ( ) 1 1 2 2 / 2 0m m v m v+ + = ur uur !?1$ 1 v ur 9 2 v uur @5694##C d(9 9 d(9 '#'G1*56##''9 394##C9!H)'J94##C93#v!H)'8 i##'7#CNO??+##S#1:?+##S#G'8 "%1 "%1 "%1 *Z7:#CNO?#156#[h ( ) ( ) ( ) 2 2 2 1 0 2 1 1 1 / 2 2 2 2 G G k l m m v V m V ∆ = + − + − ( ) ( ) ( ) 2 2 2 1 0 2 1 1 1 / 2 2 2 2 G G k l m m v V m V ∆ = + − + − 0 1 15 m l V cm k ⇒ ∆ = = "%1 "%1 "%1 #'7#S#1:#CNO? max 0 51l l l cm = + ∆ = #'7#S#G'#gNO? min 0 49l l l cm = − ∆ = "%1 "%1 "#%$(4 điểm) L&' *7' <"%1 bX " "@56#51*Q#^'#E#A3Z/ "/ "/R 1 ϕ 1*H#c 9u AB 8A?5BE9A#B^'"#$.1 9A#B(5J9V 2 2 1 2 1 2 1 2 sinI I I I I ϕ = + − ( ) 2 2 2 2 2 1 1 2 C L C C C L Z Z Z Z Z Z R Z − ⇒ = + + "%1 "%1 A?.Z3LML #51*:##[3Y'*#9?a w`!hx3Y'*#9?a8 C L C Z Z Z − = ⇔ = = C L Z Z Z ( "%1 "%1 +3E#3aMa A?.Zu AB 9i #g)\.1 9A#B(#$ I ϕ + = = L C R Z I I Z ( I #?I 8 ϕ ϕ ϕ = = + L L Z tg R Z ( \(9(#$ − + = L L C Z Z Z R ( \(9(#$ C L Z Z Z R= = = = Ω "%1 "%1 "%1 "%1 L Z rad s L ω π ⇒ = = t C C F Z ω π − = = "%1 "%1 k? C Z Z= )I4#e#C/ #vI4#e#C/ TH'1HZH'7Y1@'1?::# 8 AB C U I Z IZ V= = = ]4#e#CA3Z/ AB AB U U I A Z R = = = "%1 "%1 "%1 L&' *7' "r%1 Z'u AB #g9=iJ ( ) C L L R Z Z Z= − G5B!J9H9=aJ − < C L Z Z t ω π − ⇔ > = L C F Z "%1 "%1 "%1 2 I ur I r U ur ( 1 I ur 2 I ur I r U ur ( "#&$(4 điểm) L&' *7' "%1 k?#*C&#'G1*!2#)^'E!J7Wh#C3[ 156#OA1UE8 H1*#C3[#'j&>1@'!?!3;4156#[h i − = = "%1 "%1 H561W!'#?3[# %a y L a( ( ( = + − = − T %ai ( y − − = "%1 "%1 L&' *7' "r%1 +m MT8i#1@'EI'23[ MTd(T(" bX]Z7H#C4RO#'#?#*'j&#N:!? 4"#$ iz(]Td(M a izO(]TdO(M a i O(T O( i O(T O( i (T ( T ( − + − + ⇒ = = − + + ( "%1 "%1 "%1 *Q##A?O91:#S#1:3 i m i T O − − = = H1*Q9=E!FO!) i T( i T( ti (T ( tT ( + + = = − + + f'j&#.Z3;4JH1*#C3[ i8T T ( = + "%1 "%1 "%1 \(#$ i T O 7 7O T ( − − = + p"%1 Biện luận:L$<3.KI' 8Z'm MT{iJiqTqO'&9=XO)7' 75B"H1*'K8 8Z'iqTq({m MT|iq(JiqTqO( '75B"7'&"H1*'.8 <8Z'?+#iq(|T|iJ!?^'E!J'j&#.3;4" H1*K\ 1Z "I'1$.1Z A?I4#( "%1 "%1 "%1 "#'$(4 điểm) L&' *7' "1 bX3?.#E#c99.#C$"#$ 2 ' 2 0 d a d d d ad fa d f = + = ⇒ − + = − G :.J(.#$H\1$#$ min 18 4 a f cm = = 0E3[+#@'156#[h ( ) 1 9R f n cm = − = "%1 "%1 "%1 "%1 L&' *7' "r%1 G;W1'3H#C?EJ#g$3;2'3[#g I?I?qw.]}#h9#S# 2'3[.1+#E#]*1?:1-~M# 153[#C9HIE#v153[#C!J2'3[ "%1 "%1 "%1 L&'# *7' "%1 [I9V156#J:?9HIE!) "%1 bXk153[#C9HIE!)"#$ ' ' 0 D d d L D d + − = T ( ) ( ) 0 1 . d L d f D D d f − − = + DuI4 ( ) 2 . x x f L fL y x f − + + = 2 ' 2 . x fL y x f − = 0.Z) O ~ fL ~ } qd "%1 "%1 "%1 "%1 "%1 ] i k#$3[#5=#;23 18 3d fL cm = = bE!F#Ck min 0 2 L L D D f f = − ÷ T ( ) 6 3 2 3D cm= − "%1 "%1 "%1 . uur !?1$ 1 v ur 9 2 v uur @5694##C d(9 9 d(9 '#'G1*56##''9 394##C9!H)'J94##C93#v!H)'8 i##'7#CNO??+##S#1:?+##S#G'8 "%1 "%1 "%1 *Z7:#CNO?#156#[h ( ) ( ) ( ) 2 2 2 1 0 2 1 1 1 / 2 2 2 2 G G k l m m v V m V ∆ = + − + − ( ) ( ) ( ) 2 2 2 1 0 2 1 1 1 / 2 2 2 2 G G k l m m v V m V ∆ = + − + − 0 1 15 m l V. "%1 *K#CH!5=#9#: 2 2 1 0 0 1 2 2 3 3 m m E V V = = ÷ "%1 *K#CHI'9#: 2 2 2 1 2 1 2 3 2 G m E m V I ω = + + ÷ "%1 T 2 2 0 8 33 E. uur ( "%1 "%1 ?A^'E[149=34&#CH ( ) 2 2 2 2 1 2 2 3 11 2 12 5 3 5 15 l m I m l m l ml = + + = ÷ ÷ "%1 A?1F'.???A1*56#$ 2 2 0 2 3 11 3 5 3 / 5 15 m