Upload
ahadh12345
View
222
Download
0
Embed Size (px)
Citation preview
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
1/22
1. (a)c
xxxx
xx +++=+
23d)
243(
4
2
3
M1 A2 (1, 0) 3
(b)
2
1
4
2
3
2
1
23d)
243(
++=+
x
xxxx
x
= (6 + 16 + 1) (3 + 1 + 2) M1
= 17 A1 2[5]
2. (a) y= 9 8 42
= 0 b= 4 (*) B1 c.s.o. 1
(b) x
y
d
d
= 2 + 23
x M1
Whenx= 1 gad!en" = 2 + 1 = 1 A1#o e$%a"!on o& "he "angen" !sy ' = 1 (x 1) M1
!.e. y+x= 6 (*) A1 c.s.o. 4
(c) e"y= 0 andx= 6 soD!s (6, 0) B1 1
(d) Aea o& "!ange = 21
* ' * ' = 12.' B1
4
1 (9 2x2 21
x ) dx=
4
121
22
1
29
xxx
Ignore limits M1 A1
= (36 16 4 * 2) (9 1 4)
Use of limits M1= 12 4
= 8 A1
#o shaded aea !s 12.' 8 = 4.' A1 6[12]
3. (a) Ay= 1 By= 4 B1
(b) 2'
2
d
d x
x
y == '
2
heex= ' M1 A1
-angen" y1 = '
2
(x') ('y= 2x') M1 A1
(c) x=2
1
'y B1 B1
(d) n"ega"e
=
3
10
23
' 23
23
yy
M1 A1 &"
/
4
/ 1=
3
110
3
410 23
23
, =3
70
(233
1
, 23.3) M1 A1, A1
Holland Park School 1
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
2/22
A"ena"!e &o (d) n"ega"e 7'
3x
M1 A1
Aea = (10 * 4) (' * 1)
7'
12'
7'
1000
, = 3
70
(233
1
, 23.3) M1 A1, A1
n bo"h (d) schees, &!na M !s scoed %s!ng cand!da"es 45 and 15. [12]
4. (a) x2 2X+ 3 = 9 x M1
x2x 6 = 0 (x+ 2)(x3) = 0 x= 2, 3 M1 A1
y= 11, 6 M1 A1 &" '
(b)( ) xxxxxx 3
3d32 2
32 +=+
M1 A1
( )
+=
+
64
3
89993
3
3
2
23
xxx
= 32
21 M1 A1
-ae!% 2
1
(11 + 6) * '
=
2
142
B1 &"
Aea = 6
'20
3
221
2
142 =
M1 A1 7
A"ena"!e (9 x) (x2 2x+ 3) = 6 +xx
2M1 A1
( )32
6d632
2 xxxxxx +=+M1 A1 &"
6'20,
382129
2918
326
3
2
32
=
++
+=
+
xxx
M1 A1, A1[12]
Holland Park School 2
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
3/22
5. (a) 4x+ 9, +12 x (Ao 6x+ 6x) B1, B1 2Ao (2x)2o 4x2on !& a"e o :%s"!&!es %ndes"and!ng.
(b) ++=++ xxxdxxx 982)9124( 2
322
1
(&" de. on 3 "es) M1 A1 &"
)18)28(8(/..... 23
21 ++= (2 + 8 + 9) M1
222 23
= (seen o !!ed) B1
= 7 + 16 2 A1 '
#ec!a case M!sead as 2(x+ 3)
(a) B1 &o 4x+ 12
(b) ;%s" "he "o M as ae aa!abe.[7]
6. (a)
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
4/22
(d) 2
'
3
6
4d)'6(
23423 xxxxxxx +=+
M1 A1
a%a"!ng a" one o& "he!xa%e
=+
4
3
2
'2
4
1
M1 A1 &"
a%a"!ng a" "he o"hexa%e
=+ 41
312
12'
2'04
62'
A1
/>..' />..
1o />..
1 />..
'M1
31 4
3
4
1 = 32
-o"a Aea = 32 + 4
3
= 324
3
A1 7
If integrating t#e wrong ex!ression in (d)$ (e.g. x2% &x ' )$
do not allow t#e first M mar$ b"t t#en follow sc#eme.[14]
7. (a) #oe
32
4
1
2
3xx
= 0 "o &!nd!= 6, o e!&
32 64
16
2
3 = 0 (?) B1 1
(b) 4
33
d
d 2xx
x
y=
M1 A1
m= 9,y 0 = 9(x 6) (An coec" &o) M1 A1 4
(c) 4
33
2xx
= 0,x= 4 M1, A1&" 2
(d) 162
d42
3 4332
xxx
xx =
(Ao %ns!!&!ed es!ons) M1 A1
[ ] 2716
6
2
6.........
436
0 == M @eed 6 and 0 as !!"s. M1 A1 4
[11]
8. (a) x
y
d
d
= 3x2 14x+ 1' M1 A1 2
Holland Park School 4
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
5/22
(b) 3x2 14x+ 1' = 0 M1
(3x ')(x 3) = 0 x= >, M1, A1
(A re*"ires correct *"adratic factors).
y= 12 A1 4
(+ollowing from x , -)
(c) x= 1 y= 12 B1
#aeycood. as /(o eo gad!en"5), so/!s aae "o "hexa!s B1 2
(d)( ) xxxxxxxx 3
2
1'
3
7
4d31'7
23423 ++=++
M1 A1 A1
(+irst A - terms correct$ 1econd A all correct)
++
++=
++ 3
2
1'
3
7
4
19
2
13'63
4
813
2
1'
3
7
4
3
1
234
xxxx
M1
12
'8
4
333
24 = 2'3
1
(2 * 12) = 13
1
M1 A1 6
(or e*"i. or - s.f or better)[14]
9. (a) y= 4xx
2
x
y
d
d
= 4 2x M1 A154 2x5 = 2, x= > M1
x= 3,y= 3 A1 4
(b) xcood!na"e o&A!s 4 B1
( )
=
32
4d4
322 xxxxx
M1 A1&"
===
3
210
3
32
3
6432
32
44
0
32xx
(o eac" e$%!aen") M1 A1 '
[9]
Holland Park School 5
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
6/22
10. (a) (x 3)2, +9 !s . a= 3 and b= 9 a :%s" be !""en
don !"h no e"hod shon. B1, M1 A1 3
(b) C !s (3, 9) B1
(c) A = (0, 18) B1
x
y
d
d
= 2x 6, a"A m= 6 M1 A1
$%a"!on o& "angen" !sy 18 = 6x (!n an &o) A1&" 4
(d) #ho!ng "ha" !ne ee"s a!s d!ec" beo C, !.e. a"x= 3. A1cso 1
(e) A= x2 6x+ 18x= /31
x3 3x
2+ 18x M1 A1
#%bs"!"%"!ngx= 3 "o &!nd aeaA%nde c%eA/=36 M1
Aea o&3=A aea o& "!ange =A 2
1
* 18 3, = 9 M1 A1 '
A"ena"!e x2 6x+ 18 (18 6x)dx M1
=31
3x
M1 A1 &"
Dsex= 3 "o g!e anse 9 M1 A1[13]
11. (a) x2+ 6x+ 10 = 3x+ 20 M1
x2+ 3x 10 = 0(x+ ')(x 2) = 0 sox=, ' o 2 M1, A1
s%b a a%e &ox"o ob"a!n a a%e &oy!ny= 3x+ 20,y= ' o 26 M1, A1 '
(b) !ne c%e =, 10 3xx2
M1, A1
32
310)310(
322 xxxdxxx =
M1 A2E1E0&.".
)3
12'2'
2
3'0()
3
84
2
320(
32
310
2
'
32 +=
xxx
M1
6
1'7
6
'4'
3
111 ==
A1 7
[12]
Holland Park School 6
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
7/22
A- (b)xx
xdxxx 103
3)106( 2
32 ++=++
(1 each !ncoec" "e) M1 A2E1E0
%se o& !!"s = ( 38
+ 12 + 20) ( 3
12'
+ 7' '0) = ('1 31
) M1
Aea o& -ae!% = 2
1
(' + 26)(2 ') = (108 21 )
o 46 62.' (&o !n"ega"!on) B1&.".
#haded aea = -ae!% 6
13
12
1 '7'1108 == o 6343
o 61.'7
M1 A1 7
12. (a) x
y
d
d
= 6 + 8x3
M1 A1 2M is for x
nx
n%
in at least one term$ & or x
%-is s"fficient.
A is f"lly correct answer.
Ignore s"bse*"ent woring.
(b) 2
6d
2xxy =
+ 4x1
+ 4 M1 A1 A1 3
M 4orrect !ower of x in at least one term (4 s"fficient)
+irst A 2
&x 2
' 4
1econd A ' 5x%
[5]
13. (a)
21
3d
dx
x
y=
6 M1 A1
21
3x 6 = 0,2
1
x = 2 x= 4 (?) M1 A1 4
+irst M for decrease of in !ower of x of at least
one term (disa!!earance of 607 s"fficient)
1econd M for !"tting x
y
d
d
, 0 and finding x , 8.
Holland Park School 7
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
8/22
(b)
+=
+ xx
xxxx 103
'
4d1062 2
2'
23
M1 A1 A1
( )
+
+=
+ 103
'
440163
'
44103
'
4 2'
4
1
22
'
xxx
M1 A1&"
(= 17.6 7.8 = 9.8)
F!nd!ng aea o& "ae!% = 2
1
(6 + 2) * 3 (=12) M1 A1
/A = (1, 6), B = (4, 2)
G b !n"ega"!on
4
1
2
3
222
xx
Aea o&3=12 9.8 = 2.2 A1 8
+irst M ower of at least one term increased by
+irst A +or '
4 2E'x
1econd A +or % -x2' 0x
1econd M for limits re*"ires 9 [ ] [ ]14 9 (allow candidate:s
657)
and some !rocessing of 6integral7$[ ] 4
1y is M0
Aft re*"ires 1and 4s"bstit"ted in candidate:s 3-termed
integrand("nsim!lified)
Area of tra!e;i"m M attem!t at < (yA
' yB)(x
B% )
orx
xd
3
422
(A correct "nsim!lified)
H-IA
A""e"!ng !n"ega J( e$%a"!on o& !ne e$%a"!on o& c%e)K -h!d M1
=xxx dJ)2
3
14
3
8(J 2
3
+Fo%"h A1
Ce&o!ng !n"ega"!on F!s" M1
+ )'4
()3
7
3
8
( 2
'
2
xxx
)'
4
(2
'
xF!s" A1
+ J)
3
7
3
8(J 2xx
ao as &oo "ho%gh !n "h!s case. #econd A1
!!"s M1A1 #econd M1
-h!d A1
Anse A1 F!&"h A1[12]
14. (a)x
xxxxx '
1
8d)'82(
122
+=+
M1 A1 A1
Holland Park School 8
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
9/22
4
1
12 '
1
8
+
xx
x
= (16 2 20) (1 8 ') (= 6) M1
x= 1y= ' andx= 4y= 3.' B1
Aea o& "ae!% = 2
1
(' + 3.')(4 1) (= 12.7') M1
#haded aea = 12.7' 6 = 6.7' M1 A1 8(M 1"btract eit#er was ro"nd)
Integration =ne term wrong M A A0> two terms
wrong M A0 A0.
?imits M for s"bstit"ting limits 5 and into a c#anged
f"nction$ and s"btracting t#e rig#t way ro"nd.
Alternatie
x= 1y= ' andx= 4y= 3.' B1
$%a"!on o& !ney ' = 2
1
(x 1) y= 2
1
2
11
x, s%bse$%en"%sed !n !n"ega"!on !"h !!"s. 3
dM1
+
'
82
2
1
2
112
xxx
4"h
M1
(M 1"btract eit#er way ro"nd)
=
1
8
4
'
2
21d8
2
'
2
21 122 xxxxxx
1s M1 A1&" A1&"
(enalise integration mistaes$ not algebra
for t#e ft mars)
++=
84
'
2
21)22042(
1
8
4
'
2
214
1
12 xxx
2nd
M1
(M 3ig#t way ro"nd)
#haded aea = 6.7' A1
(@#e follow t#ro"g# mars are for t#e s"btracted ersion$
and again ded"ct an acc"racy mar for a wrong term
=ne wrong M A A0> two wrong M A0 A0.)
Holland Park School 9
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
10/22
(b) x
y
d
d
= 2 16x3
M1 A1
(nceas!ng hee) x
y
d
d
L 0 FoxL 2,3
16
x N 2, xy
d
d
L 0 dM1 A1 4
(allow )
Alternatie for t#e last 2 mars in (b)
M1 #ho "ha"x= 2 !s a !n!%, %s!ng, e.g., 2nd
de!a"!e.
A1
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
11/22
(b)166
d
d2
2
= xx
y
A"x= 2,...
d
d2
2
=x
y
M1
4 (o N 0, o bo"h), "hee&oe a!% A1&" 2M Attem!t second differentiation and s"bstit"tion of one of
t#e x al"es.
Aft 3e*"ires correct second deriatie and negatie al"e of
t#e second deriatie$ b"t ft from t#eir x al"e.
(c)( ) ++=+ )(2
20
3
8
4d208
23423 4
xxxxxxx
M1 A1 A1 3
All - terms correct M A A$
@wo terms correct M A A0$
=ne !ower correct M A0 A0.
(d)40
3
644 +
=
3
68
M1
Ax= 2 y= 8 32 + 40 = 16 (Ma be scoed esehee) B1
Aea o& =162
3
10
2
1
AAB yxx )(
2
1
=
3
32
M1
#haded aea =
==+
3
133
3
100
3
32
3
68
M1 A1 '
?imits M 1"bstit"ting t#eir lower x al"e into a c#anged:ex!ression.
Area of triangle M +"lly correct met#od.
Alternatie for t#e triangle (finding an e*"ation for t#e straig#t
line t#en integrating) re*"ires a f"lly correct met#od to score
t#e M mar.
+inal M +"lly correct met#od (beware alid alternaties)
[14]
17. (a)
4184d
d += xxx
y
xn x
n1M1 A1 2
Holland Park School 11
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
12/22
(b)( ) 2332 3
32d62
+= xxxxxx
n x
n+1M1 A1
[ ]
++= 3
32
933
32... 3
3
1
M1
= 1432
344
, 9132
o e$%!aen" A1 4[6]
18. (a) y= 0 21
x (3 x) = 0 x= 3 B1 1
o 33 23
3 = 33 33 = 0
(b)
21
21
23
23
dd xxxy =
xn x
n1M1 A1
21
21
0d
dxx
x
y==
Dse o& x
y
d
d
= 0 M1
x= 1 A1
A (1, 2) A1 '
(c)
2'
23
23
21
'
22d3 xxxxx =
M1xn xn+1 M1 A1+A1
Acce" %ns!!&!ed eess!ons &o As
Aea =[ ] 30... = 2 * 33 '
2
* 93 Dse o& coec" !!"s M1
Aea !s '12
3 (%n!"s2) A1 '
Fo &!na A1, "es %s" be coec"ed "oge"he b%" acce" eac"
e$%!aen"s, e.g.'4
27 [11]
19. (a) 2x + 4 = x23
M1
4x2 8x + 3 = 0 A1
(2x 3)(2x ) = 0 M1
x= 0.', 1.' A1 4
Holland Park School 12
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
13/22
(b)[ ] 1)13(
21o442
'.1
'.0
'.1'.0
2 ++=+ xxdxxM1
= 2 A1
'.1
'.0
'.1
'.0n
23
23
= xdxx M1 A1
=3n
23
A1&"
Aea = 2 23
n 3 A1 6
A"ena"!e so%"!on
Aea =dx
xx +
'.1
'.0 2
342M1
'.1
'.0
2 n1234
+= xxx
M1 A1 A1
o.e.3n12326
41
49 ++=
A1&"
= 2 23
n 3 A1[10]
20. (a) 23
= 2x2+ 4x M1
4x2 8x + 3(= 0) A1
(2x 1)(2x 3) = 0 M1
23
21 ,=x
A1 4
Holland Park School 13
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
14/22
(b) Aea o&3 =
23d)42(
23
21
2 + xxx(&o 2
3
) B1
( )
+=+ 232 232d42 xxxxx
(Ao O/ , acce" 2
4
x2
M1 /A1
+
+=+ 232
2
3
323
21
2
2
122
132,
2
322
332d)42( xxx
M1 M1
=
611
Aea o&3= 31
23
611 =
(Acce" eac" e$%!aen" b%" no" 0.33 ...) A1cao 6[10]
(a) 1s"M1 &o &o!ng a coec" e$%a"!on
1s"A1 &o a coec" 3-P (condone !ss!ng = 0 b%" %s" hae a "es on one s!de)
2nd
M1 &o a""e"!ng "o soe ao!a"e 3-P
(b) B1 &o s%b"ac"!on o& 23
. !"he c%e !ne5 o !n"ega ec"ange5
1s"M1 &o soe coec" a""e" a" !n"ega"!on (x
nxn+1)
1s"A1 &o 3
2
x3+ 2x
2on !.e. can !gnoe%2
3
x
2nd
M1 &o soe coec" %se o& "he! 23
as a !!" !n !n"ega
3d
M1 &o soe coec" %se o& "he! 21
as a !!" !n !n"ega and
s%b"ac"!on e!"he a o%nd
#ec!a
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
15/22
Acce"abe a"ena"!es !nc%de
3x2+ 6x
1 3x
2+ 3*2x 3x
2+ 6x + 0
gnoe Q# (e.g. %se /he"he coec" o no" o& x
y
d
d
and2
2
d
d
x
y
)
3x2+ 6x + c o 3x
2+ 6x + cons"an" (!.e. "he !""en od cons"an") !s B0 B1
M1 A""e" "o d!&&een"!a"e "he! &(x)xnRxn 1.x
nRx
n 1seen !n a" eas" one o& "he "es.
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
16/22
A""e" "o !n"ega"e &(x)xnRx
n + 1
gnoe !ncoec" no"a"!on (e.g. !nc%s!on o& !n"ega s!gn) M1
o.e.
Acce"abe a"ena"!es !nc%de
+++++++++ xxx
cxxx
xxx
xxx
'
3
3
4
M'
3
3
4
M'
3
3
4
M'
4
34341
343
4
@.B. & "he cand!da"e has !""en "he !n"ega (e!"hex
xx'
3
3
4
34
++
o ha" "he "h!n !s "he !n"ega) !n a" (a), !" a no" be e!""en
!n (b), b%" "he as a be aaded !& "he !n"ega !s %sed !n (b). A1
#%bs"!"%"!ng 2 and 1 !n"o an &%nc"!on o"he "hanx3+ 3x
2+ '
and s%b"ac"!ng e!"he a o%nd.
#o %s!ng "he! &(x) o &(x)o "he! &(x)dx o "he! &(x)dx! ga!n "he M a (beca%se none o& "hese ! g!e x
3+ 3x
2+ ').
M%s" s%bs"!"%"e &o axs b%" co%d ae a s!.
4 + 8 + 10 41
+ 1 + ' (&o eae) !s acce"abe &o e!dence
o& s%b"ac"!on (S!n!s!be bace"s). M1
o.e. (e.g. 1'4
3
, 1'.7', 4
63
)
M%s" be a s!nge n%be (so 22 64
1
!s A0). A1
Anse on !s M0A0M0A0
aes
cxxx
+++ '4
34
M1A1 4
4x
+x3+ 'x + cM1 A1
4 + 8 + 10 + c (4
1
+ 1 + ' + c) M1 x = 2, 22 + c
= 1'4
3
A1 x = 1, 64
1
+ c M0 A0
(no s%b"ac"!on)
)'31('232d)&( 23
2
1++++= xx M0A0, M0
= 2' 9
= 16 A0
(#%bs"!"%"!ng 2 and 1 !n"ox3+ 3x
2+ ', so 2nd M0)
Holland Park School 16
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
17/22
[ ]2122
1
63d)66( xxxx +=+M0 A0
[ ]21232
1
2 3d)63( xxxxx +=+M0 A0
= 12 + 12 (3 + 6) M1 A0 = 8 + 12 (1 + 3) M1 A0
4
4x
+x3
+ 'x M1 A1
'14
12'2
4
2 34
34
++++M1
(one nega"!e s!gn !s s%&&!c!en" &o e!dence o& s%b"ac"!on)
= 22 6 4
31'
4
1 =A1
(ao Secoe, !!ng s"%den" as %s!ng S!n!s!be bace"s)
(a) &(x) =x3+ 3x
2+ '
&(x) =xxx '
43
4
++B1M0A0
(b)'1
4
12'2
4
2 34
34
++M1A1M1
= 1'4
3
A1
-he cand!da"e has !""en "he !n"ega !n a" (a). " !s no" e!""en
!n (b), b%" "he as a be aaded as "he !n"ega !s %sed !n (b).[7]
22. y =x(x2 6x + ')
=x3 6x
2+ 'x M1, A1
2
'
3
6
4d)'6(
33423 xxx
xxxx +=+M1, A1&"
4
30
2
'2
4
1
2
'2
4
1
0
23
4
=
+=
+ xxx
M1
411
43)10164(
2'2
4
2
1
2
3
4
=+=
+ xxx
M1, A1(bo"h)
"o"a aea = 411
4
3+
M1
2
7=
o.e. A1cso 9
Holland Park School 17
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
18/22
A""e" "o %"! o%", %s" be a c%b!c. M1
Aad A a &o "he! &!na es!on o& eans!on (b%" &!na es!on
does no" need "o hae !e "es coec"ed). A1
A""e" "o !n"ega"exnxn+1. Teneo%s a &o soe %se o&
!n"ega"!on, so e.g.
= xx
x
xx
xxxx '222d)')(1(
222
o%d ga!n e"hod a. M1
F" on "he! &!na es!on o& eans!on o!ded !" !s !n "he &o
ax!
' bx*+ ....
n"egand %s" hae a" eas" "o "es and a "es %s" be !n"ega"ed
coec".
& "he !n"ega"e "!ce (e.g.2
1
1
0
and
) and ge" d!&&een" anses, "ae
"he be""e o& "he "o. A1&"
#%bs"!"%"es and s%b"ac"s (e!"he a o%nd) &o one !n"ega.
n"ega %s" be a Schanged &%nc"!on. !"he 1 and 0, 2 and 1 o 2 and 0.
Fo[ ]1
0 0 &o bo""o !!" can be !!ed (o!ded "ha" !" !s 0). M1
M1 #%bs"!"%"es and s%b"ac"s (e!"he a o%nd) &o "o !n"egas.
n"ega %s" be a Schanged &%nc"!on. M%s" hae 1 and 0 and 2 and 1
(o 1 and 2).
-he "o !n"egas do no" need "o be "he sae, b%" "he %s" hae
coe &o a""e"s "o !n"ega"e "he sae &%nc"!on. M1
+=
2
1
23
4
2
1
1
2
2
1
.2
'2
4)&(hee))&(
o)&(o)&(%s!ng(!&o4
11and
4
3o))&(%s!ng(!&o.e.
4
11and
4
3
xx
xxx
xxx
-he anse %s" be cons!s"en" !"h "he !n"ega "he ae %s!ng
(so =
2
1 4
11)&(x
oses "h!s A and "he &!na A).
4
11
a no" be seen e!c!".
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
19/22
'"h
M1 J "he! a%e &o[ ] [ ]2
1
1
0 &o%e"he! a+
Ueenden" on a" eas" one o& "he a%es co!ng &o !n"ega"!on
(o"he a coe &o e.g. "ae!% %es).
-h!s can be aaded een !& bo"h a%es aead os!"!e. M1
2
7
o.e. @.B. c.s.o. A1 cso[9]
23.
=
2
1d
2
1
2
1x
xx
(G e$%!aen", s%ch as xx 2o,2 2
1
) M1A1
242282
2
1
8
1
2
1
+==
x
/o 42 2, o 2(22 1), o 2(1 + 22) M1A1 4
1s"M1
2
1
2
1
)xx
, 0.
2nd
M #%bs"!"%"!ng !!"s 8 and 1 !n"o a Schanged &%nc"!on
(!.e. no"
2
1
o1
xx ), and s%b"ac"!ng, e!"he a o%nd.
2nd
A -h!s &!na a !s s"! scoed !& 2 + 42 !s eached !a a dec!a.
Holland Park School 19
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
20/22
@.B. n"ega"!on cons"an" +4a aea, e.g.8
1
2
1
2
1
+
4x
= (28 + 4) (2 + 4) = 2 + 42 (#"! &% as)B%"... a &!na anse s%ch as 2 + 42 + 4!s A0.
@.B. " ! soe"!es be necessa "o S!gnoe s%bse$%en" o!ng
(!s) a&"e a coec" &o !s seen, e.g.
=
2
1d
2
1
2
1x
xx
(M1 A1),
&ooed b !ncoec" s!!&!ca"!on
=
=
2
12
1
2
1
2
1
2
1d x
xxx
(s"! M1 A1).... -he second M a !s s"! aa!abe &o
s%bs"!"%"!ng 8 and 1 !n"o
2
1
2
1x
and s%b"ac"!ng.[4]
24. (a) !"he so!ng 0 =x(6 x) and sho!ngx= 6 (andx=0) B1 1
(b) o sho!ng (6, 0) (andx= 0) sa"!s&!esy = 6xx2
/ao &o sho!ngx= 6
#o!ng 2x = 6xx2(x
2= 4x) "ox= >. M1
x = 4 ( andx= 0) A1
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
21/22
(c) (Aea =)
)4(
)0(
2 d)6( xxx!!"s no" e$%!ed M1
8/13/2019 Core 2 - Ch 11 - 1 - Integration - Solutions
22/22
-he &!na a a aso be scoed b e!&!ng "ha"0
d
d=
x
y
a"x= 2.
(b) Aea o& "!ange =222
2
1 (M