U I = I = I = = 1 R R 40 U=.5V P=0.5 R= U P =.5 05.

P=UIP=IRP= U t R

I = U, R = U, U = I R R I

sh x w r ao

i [i:] ei [-!] e [+:] ou [+( ] a [%:] ai [%!] o [&:] au [%( ] u [( :] oi [&!] p [p] h [h] b [b] f [f] t [t] s [s] d [d] ng [R] k [k] w [w] g [g] sh [M;:] m [m] cg [CM] n [n] zh [dr] l [l]

= 141411. Λ. ( 1) ( 4) ( 1) ( 4) ( ) ( 1) 3 = 1.73

in after in after in after in five months in three minutes I can go to work in a day or two. after May after three o clock 1988 after 1988 I ll phone you after I arrive. x x = 3 8 1 0, x1 + x = 0, 4 3 + 3 x 4x + c = 0 c [ 35 1 ( )] x 1 x1 + + 3 = 4x 1 = 3 c = ( + 3)( 3) = 1 3 c = 1

3 x1 x 4x x 5 = 0 x x + x x 1 5 1 5 x + x = 1 5 1 x1 x 4 = 4 5 5 3 3 x 1x + x1 x = x1x ( x1 + x) = ( x1x ) ( x1 + x)( x1 x1x + x) = ( x1x ) ( x1 + x)[( x1 + x ) 3x1x ] 5 1 1 5 = ( ) [( ) 3( )] 4 4 4 4 155 = = 1 501 104 104 5 5 x1 x + x1 x 1 510 104 1 4 1 (, ) x 3 x + 1 = 0 1 + 1 = 3 1 1 1 1, = (, 1) 1 1 5, 3 1 1 1 1 x ( + ) x + = 0 3 3 6x 5x + 1= 0 x1 = 3 7 x = 3 + 7 3 7 3+ 7 x 3x 1 = 0 x1 x x x x + x = 3 x x = 1 1 1 1 1 1 1 1 x 1 + x = ( x + x ) x x = 3 ( 1) = 11 x x = ( x x ) = ( ) = 1

b c b c t + 3t = t 3t = 5t = 6 t = a a a a 10 9 m 3x + x + m = 0 9 10 m x 1 + x = x 1 + x = = x 1 x 9 3 3 ( x1 + x ) ( x1 + x ) m = 3x1x = 3 3 10 3 = [( ) ] = ( ) = 1 3 9 3 10 m = 1 9 m n x + y = m x y = n x y m n = xy ( x y 0) 10 14 + 6 5 14 + 6 5 = 14 + 45 14 + 45 = 9 + 5 = 3 + 5 14 + 6 5 = 3 + 5 x + x 1 13 11 x + 1 + + = x + 6 x + x 1 13 m n m n m n 1 x + 1 = + = + = = x + 6 13 m n y y + 1 = 0 6 3 3 3 y1 = y = m = n = 3 3 3 x + x x x x + = 3 = 1 + 1 3 14 1 = = 1 5 x + 5

x + y = 5 1 xy = 1 x1 = 3 x = 4 x 3 = 3 x4 = 4 y1 = 4 y = 3 y 3 = 4 y4 = 3 199 1990 1 ( 3 + ) ( 3 ) = = ( 3 + ) ( 3 + ) ( 3 ) 1990 = ( 3 + ) [( 3 + )( 3 )] = ( 3 + ) = 5+ 6 1990 1990 a + b + c + 3 = ( a + b + 1 + c 1) a + b + c = ( 199 ) ( 1990 ) [( a) a + 1] + [( b + 1) b + 1 + 1] + [( c 1) c 1 + 1] = 0 ( a 1) + ( b + 1 1) + ( c 1 1) = 0 ( a 1) = 0 ( b + 1 1) = 0 ( c 1 1) = 0 a = 1 b = 0c = a + b + c = 1 + 0 + = 5

1 1 x y 3 x = y = + 7 + 5 7 5 y x ( 199 ) 1 1 x = = ( 7 5) 7 + 5 1 1 y = = ( 7 + 5) 7 5 1 x + y = 7xy = x + y xy x y x + y ( x + y) xy + = = y x xy xy 1 ( 7) = = 1 1 5 + 7 4 10 + 14 + 15 + 1 ( 1989 ) 5 + 7 = ( 10 + 15) + ( 14 + 1) 5 + 7 = 5( + 3) + 7( + 3) 5 + 7 = ( + 3)( 5 + 7) 1 = = 3 + 3 6 + 4 3 + 3 5 ( 6 + 3)( 3 + ) ( 1986 ) 6 + 3 + 3( 3 + ) = ( 6 + 3)( 3 + ) 6 + 3 3( 3 + ) = + ( 6 + 3)( 3 + ) ( 6 + 3)( 3 + ) 1 3 = + 3 + 6 + 3 = 3 + 6 3 = 6

x 3+ 3 6 6 = 1+ 3 ( ) 3 1 + + 1 3 6 = + + + 1 + 3 ( 1+ ) + ( + ) ( 3 + 6) = 1+ 3 ( 1+ ) + ( 1+ ) 3( 1+ ) = 1+ 3 ( 1+ )( 1+ 3) = = 1+ 1+ 3 6 7 + 3 + 5 ( 35 ) ( + 6 + 3) 5 ( + 3) ( 5) = = + 3 + 5 + 3 + 5 5 + + 5 8 3 = ( ) 5 + 1 5 5 ( A) 1( B) 1( C) ( D) ( E) ( 1987 ) 5 + + 5 x = 5 + 1 5 + = = x = 5 + 1 = ( 1) = ( 1) = 1 ( A) 9 11+ 6 + 11 6 ( ) 11 + 6 0 11 6 0 11 + 6 + 11 6

= ( 11+ 6 + 11 6 ) = + 11 ( 6 ) = 36 = 6 10 ( 10 + 5 + 1) + ( 10 5 + + 1) = [( 10 + ) + ( 5 1)] + [ 10 + ) ( 5 1)] = ( 10 + ) + ( 5 1) = 4( 5 + 1) + ( 5 1) = 4( 6+ 5) + ( 6 5) = 36+ 4 5 11 P = 1988198919901991+ 1 + ( 1989 ) P ( ) P = ( a 1) a ( a + 1)( a + ) + 1 + ( a ) = ( a 1)( a a) + 1 a = a + a a a + 1 a 4 3 4 3 = a + a + 1+ a a a a = ( a + a 1) a = a + a 1 a = a 1 = 1989 1 = 1988 ( B) 5 1 4 1 x = x + x + x 1 = ( 1990 ) 5 1 x = x + 1 = 5 4 x + x 1 = 0 x + x + x 1 = ( x + x 1)( x x + 3) x + = x + 5 1 = + = 3 5 ( )

R = C BC AD Φ Α ΒΧ EF = EF

a b c r = + FG CMN FG = ΜΝ = AN + BM AB = AC + BC AB FG AC BC AB + a b c = r = + Rt ABC 13 1 1

O AD = 3 OD = 3a 9 AB AD = 3 AD AB = = 3a 3 BAC BP + QC PQ

BAC QAM = PAQ = AMQ APQ = PQ QCM + QCMQ BP + QCPQ 1 AD = CE DE BC 1 DEBC S = 1 CFAB = 1 BEAC ABC CF AC = 1 CFBE BE AB

1 OP AD 1 OPAD

DE AD y 8 x = = 5 y = x + 10 0 x 8 BC AB 10 8 4 40 ( )( y = ) 49 1 1 1 = + r r r 3 1

O D = r r O E = r r O F = r r 1 3 1 3 3 3 OD = EF = O3E + O3F r1r = r1r3 + rr3 1 1 1 = + r r r 3 1 3 CA D E F AB = 5 A ( 1) O 5 ( ) ABC AC = AB COSA = 5 3 = 3 BC = 4 5 AC + BC AB 3 CE = CF = = + 4 5 = 1 O 1 ( )S = S ABC S OECF S OFDE 1 70π 1 3 = 3 4 1 = 5 π 360 4

1 ABC + DAB = 180 ABO = ABC 1 OAB = DAB ABO + OAB = 90 AOB = 90 MPN = 90 AOB = MPN = 90

1 = S = πr OCD 6 a a π ( )

a 1 [ a π ( ) ] = a πa 1 = a ( a a ) = ( 1) a 1 a S 1 a a = 8 [ ( ) ] = ( 1) a 4 = 1 1 6 6 = 3 ( )

lh1 ah = ( l a) a = h1 + h lh1h S = = h + h 1 3 1 PAD 1 S PBD = S ABD S BAP S PAD. 1 1 S ABD =, S BAP =, 4 1 S PAD = ( 4 3 ). 1 1 1 1 S PBD = 3= 3 1 4 4 4

BE = 3. DE = 3. S ABCD = S ABE S CDE 1 1 = 3 13 = 3 3. BD = 3 + 4 = 5 1 1 S ABCD = S ABD + S BCD = ADBD + DCBC 1 = + = 1 5 1 4 3 36

15cm 9cm 1cm PA S ABP 15 5 = = = PC S 9 3. CBP S ADP PA S S cm S = ADP CDP PC = 5 = 5 = 5 3 3 3 1 = 0. ( ) CDP 4x + 4y = a, 1 x + y = πa, 8 π 4, 4x = ( 1) a. π 1 a.

ρ V V = V ρ V 1 V V = V V1 G F = G G = ρ Vg m V m G G = = ρ= ρ ρ g G G 5 G G G F = G G = ρ V g F = G + G G = ρ V g G V = V + V V = gρ

G 4 ρ = ρ G G ρ < ρ G G G G + G G + G = G + G G + + + + K Ca Na KOH NaOH Ba( OH) Ca( OH) NH H O 3 H SiO 3

He Ke C Cu As Se Cs Tl Cr H N O Na Sb Pd

(1 ) () ( ) () ( ) () 1 11 10 8 7 5 4 3 0 (11 ) (9 ) (4 ) () ( ) () ( ) () 11 10 9 8 7 5 4 3 0 9 8 7 6 5 4 3 1 0 4 3 1 0

1 m 1 m m ( A) M ; ( B) M; ( C) m; ( D) m.

4 m m 3 m 6 4 0 5 13 15 ( A) ; ( B) ; ( C) ; ( D). 13 3 8 8 m m 3 = 6 4 m = 13 C 8 m = 15 D 8 x 1 3 x = x + x 3 ± 1 > 0 m > 4 m > 1 m 0 4 β α 5 α β x + 5x + = 0 + α β β α 5 + = α β β α β α + = ± 5 α β α β β α + = 5 α β m m 9 6 y=( m+) x m

1 1 y x y = 1 x + 1 x A ( 0 1) B ( 15, 39) ΑB 8 x 8x ( 10 m ) x+ m 7= 0 10 = m 7 m 0 0 m = 10 x 8 1 x 0 10 m = 0 ±

± x( y+ z x) = 39 x, 5 y( x+ z y) = 5 y, z( x+ y z) = 78 z. ±

ACX = ABE AXC ΑΕΒ CAX = BAE ACX = ABE B AXE = ACB AXE = 90 EXB = 90 AB ACB = 90 AB ADB = 90 BDX = BAE BDX ABE ABBD = BEXB DBX = ABE

BAX = CAD AC AB ADC AXB = DCA = XBA CD BX ADX = ACB AC AD ADX ACB = DAX = CAB BC XD AB AC AM + = AP AQ AN ( 1) AB ( ) AP = AX AC AN AQ = AY AN

BXPN ABAP = AXAN AB AC AX + AY + = CYNQ ACAQ = AYAN AP AQ AN BXYC XBM = YCM BXPQ BM = MC BXM YCPQ XMB = YMC CYM XM = MY AX = AM MX AX + AY = AM AY = AM + MY AB AC AM + = AP AQ AN 3

S CMN = x CM 3 + y = BM BMN S S S AMC x y CM = + + 1 = 5 BM S S OMN OBM AMB y = = 3 ON OB S S OAN OAB 1 = = x + y + 1 x = 5 3 + y ON OB y 1 = y = 3 3 45 45 GH FD AD tg A AC sinα tg A = = = = AC tg A = CE sinα sinα sinα sinα

T G + = G = 600+ 300 = 5 4 4

Q cm, t t 1 Q1 c1m1 Q1 c m 5q c V 1 039. 89. 10 = = = = Q Q c1 m1 10q c1 1 V 046. 7. 9 10 c m 3 3 R R R R R R = R 1 R R 0 = 0 0 R R R 1 0 = = + + 3 3 0 0 0

I U/ R R U Ι = U R I = R U R = R = / 3 0 / R = 3 9 0 Q t = t 1 U I = I cm t R I I = I 9 I I = = 9 = 9 9

1 1 1 R = R1 + R+ R 3 = 3 + 6 + 9 = 18 = + R R R R 3 1 1 1 1 1 11 18 + = + + = R = 3 6 9 18 11

1 3 4 5 6 7

G ρ = ρ G G' G ρ = ρ G G G ρ = ρ F + G

G G G = = G G G G G ρgv = G G gv = G G = ρ G G m m ρ gv = ( m m g ρ ρ ρ 1 ) = = V m m 1

+ 1 x 40 15% 40+x 10% 40 15%=(40+x)10% 30% x 30% x+769 0.05% x 30%=(x+769)0.05% 1059 x 3 x x 30% x+0 10% x 30%=(x+0)10% 100% 100% + 4 0 100%-15% 0+x 100%-0% 0 (100%-15%)=(0+x) (100%-0%) x 5 x 100%-8% x+6 100%-40% x (100%-8%)=(x+6)(100%-40%) x

- 6 40 1.5% 40-x 0% 40 1.5%-(40-x)0% x 7 x x 0.5% x-36 30% x 0.5%=(x-36)36% 1 x y 1 3 1 x y 1 ( x y) 3 = 3 x 3y = 1 x y ( x y)

1 ( x y) 6 = 3 x 6y = 1 3x 6y ( x y) 6 x + 1 ( x + ) 3x x + = x + x = + 1 3x 3x x = + 1 1 x x + x + = 1 3 3x( x + ) x 4 3 x x + 5x + 6 x 4 x x x x + 5x + 6 = ( + )( ) = ( x + 3)( x + ) x + 3 x 4 x 3 x + 5x + 6 x 4 x x 3 x + 5x + 6 a 1 4 a a + a 3

1 5 x 1 1 x 1 1 = 0 x = 1 x 1 x 1 x m 6 x 3 x 1 = m 3 m m 3 x = + 3 m 0 m = 0 x x 1 = 3 3 m m 0 x 3 x = + 3 m