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MATH 1004 - Tests 1, 2, 3, 4, 5, 6 Winter 2019
Calculus for Engineering or Physics (Carleton University)
Studocu is not sponsored or endorsed by any college or university
MATH 1004 - Tests 1, 2, 3, 4, 5, 6 Winter 2019
Calculus for Engineering or Physics (Carleton University)
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1
School of Mathematics and Statistics
Carleton University
Math. 1004A, Winter 2019
TEST 1
SOLUTIONS
Any wireless calculator permitted, 1 or more blank sheets permitted for roughs
Print Name :
Student Number:
Tutorial Section (H1, H2, H3, H4):
PART I: Multiple Choice Questions
(Choose and CIRCLE only ONE answer - No part marks here.)
1.
[2 marks]
Evaluate
lim
x
→∞
parenleftbigg
2
x
+ 10
-
12
parenrightbigg
.
(a) 1,
(b) 0,
(c) 10
-
1
,
(d) 10
-
12
Answer: (d)
2.
[2 marks]
Evaluate
lim
x
→∞
x
sin
x.
(a) 0,
(b) 1,
(c)
−
1,
(d) The limit does not exist
Answer: (d)
3.
[2 marks]
Evaluate lim
x
→
0
sin(2 sin
x
)
sin
x
.
(a) 1
/
2,
(b) 2,
(c) 0,
(d) 1,
(e) None of these or the limit does not exist.
Answer: (b)
4.
[2 marks]
Which of the following functions is continuous at
x
= 0?
(a)
f
(
x
) =
1
x
,
(b)
f
(
x
) =
|
x
|
,
(c)
f
(
x
) =
x,
for
x
negationslash
= 0 and
f
(0) = 1,
(d) None of these.
Answer: (b)
5.
[2 marks]
Evaluate lim
x
→
0
1
−
cos(
x
2
)
x
2
.
(a)
−
1,
(b) 1
/
2,
(c) 0,
(d) 1,
Answer: (c)
PART II: Show all work here and give details.
No additional pages will be accepted
6.
[5+5 marks]
a)
A function
f
has the property that
f
(0) = 1,
f
(1) =
−
1,
f
(
−
1) = 2 and
f
(2) = 0. Evaluate the composition
f
(
f
(
f
(0))).
Answer:
f
(
f
(
f
(0))) =
f
(
f
(1)) =
f
(
−
1) = 2
.
b) Let
f
be defined by
f
(
x
) =
braceleftbigg
x,
if
x
≥
0
,
1
,
if
x<
0
.
Find lim
x
→
0
f
(
x
). Give details for your answer.
Answer:
The limit does not exist because the left and right limits at
x
= 0 are different.
For example,
lim
x
→
0
-
f
(
x
) = 1 while lim
x
→
0
+
f
(
x
) = 0.
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2
.
7.
[5+5 marks]
Evaluate the following limits and give reasons. (An answer without details is insufficient for full marks)
a) lim
x
→
3
x
−
3
x
2
−
9
b) lim
x
→
0
x
|
x
|
Answer:
a) For
x
negationslash
= 3,
x
−
3
x
2
−
9
=
x
−
3
(
x
−
3)(
x
+ 3)
=
1
x
+ 3
and so lim
x
→
3
x
−
3
x
2
−
9
= lim
x
→
3
1
x
+ 3
=
1
6
.
b) For
x >
0,
|
x
|
=
x
, by definition, so
x
|
x
|
= 1 which implies that
lim
x
→
0
+
x
|
x
|
= 1 as well. On the other hand, for
x <
0,
|
x
|
=
−
x
, by definition, so
x
|
x
|
=
−
1 and this implies that
lim
x
→
0
-
x
|
x
|
=
−
1. Since the right and left hand
limits at
x
= 0 are different the required limit does not exist.
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1
School of Mathematics and Statistics
Carleton University
Math. 1004A, Winter 2019
TEST 2
SOLUTIONS
Any wireless calculator permitted, 1 or more blank sheets permitted for roughs
Print Name :
Student Number:
Tutorial Section (H1, H2, H3, H4):
PART I: Multiple Choice Questions
(Choose and CIRCLE only ONE answer - No part marks here.)
1.
[2 marks]
Evaluate lim
h
→
0
f
(
h
)
−
f
(0)
h
where
f
(
x
) =
x
|
x
|
, for all
x
.
(a) 2,
(b) 0,
(c)
−
1,
(d) The limit does not exist
Answer: (b)
2.
[2 marks]
Let
f, g
be two differentiable functions such that
f
′
(0) = 2,
g
(1) = 0,
g
′
(1) =
−
1 and
f
(1) = 0. Evaluate
(
f
◦
g
)
′
(1)
.
(a)
−
2,
(b) 0,
(c) 2,
(d) 1
Answer: (a)
3.
[2 marks]
Evaluate lim
x
→
0
sin(Arcsin
x
)
Arcsin
x
.
(a)
π
,
(b) 0,
(c) 1,
(d)
−
1,
(e) None of these or the limit does not exist.
Answer: (c)
4.
[2 marks]
Which of the following functions is differentiable at
x
= 0?
(a)
f
(
x
) =
|
x
|
,
(b)
f
(
x
) = 1
/x
,
(c)
f
(
x
) =
x
2
|
x
|
,
(d)
f
(
x
) =
x
|
x
|
for
x
negationslash
= 0 and
f
(0) = 1.
Answer: (c)
5.
[2 marks]
Let
x
2
+ 3
xy
2
+ sin(
y
) = 0 describe a curve in the plane. Assuming that
y
can be written as a function of
x
calculate its derivative,
y
′
, at the point
x
= 0
, y
=
π
.
(a)
π
,
(b)
−
1,
(c)
−
π
2
,
(d) 3
π
2
,
Answer: (d)
PART II: Show all work here and give details.
No additional pages will be accepted
6.
[5+5 marks]
a) Write down the formula for the derivative,
F
′
, of an inverse function
f
in terms of
f
′
and
F
.
Answer:
F
′
(
x
) =
1
f
′
(
F
(
x
))
.
b)
Use the result in (a), above, to show that if a differentiable function
f
with an inverse
F
has the property that
f
(
−
1) = 1,
f
′
(
−
1) = 1
/
3,
f
(1
/
3) = 2 and
f
(0) = 1. Evaluate the derivative
F
′
(1).
Answer:
Since
f
(
−
1) = 1 it follows that
F
(1) =
−
1. On the other hand,
F
′
(1) =
1
f
′
(
F
(1))
=
1
f
′
(
−
1)
= 3
.
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2
.
7.
[5+5 marks]
a) Let
f
(
x
) = Arctan(sin(
x
2
)). Evaluate
f
′
(
√
π
).
b) Find the derivative of the function
g
(
x
) = sin(Arcsin (
√
cos
x
)) at
x
= 0.
Answer:
a)
f
′
(
x
) =
1
1 + sin
2
(
x
2
)
2
x
cos(
x
2
) =
⇒
f
′
(
√
π
) =
−
2
√
π
Answer:
b) Since sin(Arcsin
x
) =
x
for all
x
=
⇒
g
(
x
) =
√
cos
x
. So,
g
′
(
x
) =
−
1
2
(cos
x
)
−
1
/
2
sin
x
and
g
′
(0) = 0.
Total: 30 marks
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1
School of Mathematics and Statistics
Carleton University
Math. 1004 H, Winter 2019
TEST 3
No wireless calculators, 1 or more blank sheets permitted for roughs
Print Name :
Student Number:
Tutorial Section (H1, H2, H3, H4):
PART I: Multiple Choice Questions
(Choose and CIRCLE only ONE answer - No part marks here.)
1.
[3 marks]
A continuous function
f
has an antiderivative
F
such that
F
(0) = 1,
F
(1) = 2 and
F
(2) =
-
1. Evaluate
the definite integral
integraldisplay
2
0
f
(
x
)
dx
.
(a) 0,
(b)
-
2,
(c) 3,
(d) 1.
Answer: (b)
2.
[3 marks]
Find the most general antiderivative of
x
3
x
2
, that is, evaluate
integraldisplay
x
3
x
2
dx
.
(a)
3
x
2
3 log 2
+
C
,
(b)
3
x
2
−
1
2 log 3
+
C
,
(c)
3
x
2
−
1
log 3
+
C
,
(d)
3
x
2
2 log 3
+
C
,
Answer: (d)
3.
[3 marks]
Find the antiderivative
F
of
f
(
x
) = sin
3
x
cos
x
such that
F
(0) =
-
1.
(a)
sin
4
x
4
-
1,
(b)
cos
4
x
4
-
5
4
,
(c)
sin
4
2
x
4
-
1,
(d)
sin
3
x
3
-
1.
Answer: (a)
4.
[3 marks]
Evaluate
integraldisplay
xe
2
x
dx
.
(a)
xe
2
x
8
-
e
2
x
4
+
C
,
(b)
xe
2
x
4
-
e
2
x
2
+
C
,
(c)
xe
2
x
2
-
e
2
x
4
+
C
,
(d)
xe
2
x
2
-
e
2
x
2
+
C
,
(e) None of these.
Answer: (c)
5.
[3 marks]
Let
f
be a differentiable function with
f
(0) = 1 and
integraldisplay
f
′
(
x
)
dx
=
x
2
+
C
where
C
is a constant. Then
f
(
x
) =
x
2
+ 1.
(a) TRUE,
(b) FALSE,
Answer: (a)
PART II: Show all work here and give details.
No additional pages will be accepted
6.
[5+5 marks]
a) Evaluate
integraldisplay
1
0
xe
−
x
dx
.
b) Evaluate
integraldisplay
3
x
2
sin
xdx
.
Answer: (a)
The Table Method gives,
integraldisplay
1
0
xe
−
x
dx
=
(
-
xe
−
x
-
e
−
x
)
vextendsingle
vextendsingle
vextendsingle
vextendsingle
1
0
= 1
-
2
e
.
Answer: (b)
Once again the Table Method gives
integraltext
3
x
2
sin
xdx
=
-
3
x
2
cos
x
+ 6 cos
x
+ 6
x
sin
x
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2
.
7.
[2+3 marks]
a) Evaluate
lim
x
→
0
+
d
dx
integraldisplay
x
2
1
sin
t
t
3
/
2
dt
using Leibniz’s Rule.
b) Evaluate
integraldisplay
2
0
t
1 +
t
4
dt
using any method.
(Hint: Think arctangent)
Answer: (a)
Using Leibniz’s Rule, we get, for
x >
0,
d
dx
integraldisplay
x
2
1
sin
t
t
3
/
2
dt
=
sin
x
2
x
3
2
x
-
0 = 2
sin
x
2
x
2
.
Since,
lim
x
→
0
sin
x
2
x
2
= 1, it follows that
lim
x
→
0
+
d
dx
integraldisplay
x
2
1
sin
t
t
3
/
2
dt
= 2 lim
x
→
0
sin
x
2
x
2
= 2
.
Answer: (b)
Let
u
=
t
2
,
du
= 2
tdt
or
tdt
=
du
2
.
For
t
= 0,
u
= 0 while for
t
= 2,
u
= 4.
Hence,
integraldisplay
2
0
t
1 +
t
4
dt
=
1
2
integraldisplay
4
0
du
1 +
u
2
=
1
2
Arctan
u
vextendsingle
vextendsingle
vextendsingle
vextendsingle
4
0
=
1
2
Arctan 4
.
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lOMoARcPSD|31437612
1
School of Mathematics and Statistics
Carleton University
Math. 1004 H, Winter 2019
TEST 4
Any wireless calculator permitted, 1 or more blank sheets permitted for roughs
Print Name :
Student Number:
Tutorial Section (H1, H2, H3, H4):
PART I: Multiple Choice Questions
(Choose and CIRCLE only ONE answer - No part marks here.)
1.
[3 marks]
A continuous function
f
has an antiderivative
F
such that
F
(0) = 1,
F
(1) = 2 and
F
(2) =
-
1. Evaluate
the definite integral
integraldisplay
2
0
f
(
x
)
dx
.
(a) 0,
(b)
-
2,
(c) 3,
(d) 1.
Answer:
(b)
2.
[3 marks]
Find the most general antiderivative of
x
3
x
2
, that is, evaluate
integraldisplay
x
3
x
2
dx
.
(a)
3
x
2
3 log 2
+
C
,
(b)
3
x
2
−
1
2 log 3
+
C
,
(c)
3
x
2
−
1
log 3
+
C
,
(d)
3
x
2
2 log 3
+
C
,
Answer:
(d)
3.
[3 marks]
Find the antiderivative
F
of
f
(
x
) = sin
3
x
cos
x
such that
F
(0) =
-
1.
(a)
sin
4
x
4
-
1,
(b)
cos
4
x
4
-
5
4
,
(c)
sin
4
2
x
4
-
1,
(d)
sin
3
x
3
-
1.
Answer:
(a)
4.
[3 marks]
Evaluate
integraldisplay
xe
2
x
dx
.
(a)
xe
2
x
8
-
e
2
x
4
+
C
,
(b)
xe
2
x
4
-
e
2
x
2
+
C
,
(c)
xe
2
x
2
-
e
2
x
4
+
C
,
(d)
xe
2
x
2
-
e
2
x
2
+
C
,
(e) None of these.
Answer:
(c)
5.
[3 marks]
Let
f
be a differentiable function with
f
(0) = 1 and
integraldisplay
f
′
(
x
)
dx
=
x
2
+
C
where
C
is a constant. Then
f
(
x
) =
x
2
+ 1.
(a) TRUE,
(b) FALSE,
Answer:
(a)
PART II
Show all work here and give details.
Answers only are insufficient for full credit.
No additional pages will be accepted
6.
[5+5 marks]
a) Evaluate
integraldisplay
1
0
xe
−
x
dx
.
Answer:
Use Table method to get
integraldisplay
xe
−
x
dx
=
-
xe
−
x
-
e
−
x
so that
integraldisplay
1
0
xe
−
x
dx
=
-
xe
−
x
-
e
−
x
vextendsingle
vextendsingle
vextendsingle
vextendsingle
1
0
= 1
-
2
e
b) Evaluate
integraldisplay
3
x
2
sin
xdx
.
Answer:
Table method of integrating by parts is easiest!
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2
This gives
integraldisplay
3
x
2
sin
xdx
=
-
3
x
2
cos
x
+ 6
x
sin
x
+ 6 cos
x
+
C
7.
[2+3 marks]
a) Evaluate
lim
x
→
0
+
d
dx
integraldisplay
x
2
1
sin
t
t
3
/
2
dt
using Leibniz’s Rule.
Answer:
Let
f
(
t
) =
sin
t
t
3
/
2
.
Then, by Leibniz’s rule, we get
d
dx
integraldisplay
x
2
1
sin
t
t
3
/
2
dt
=
d
dx
integraldisplay
x
2
1
f
(
t
)
dt
=
f
(
x
2
)
·
(2
x
)
-
f
(1)
·
0 = 2
x
sin
x
2
x
3
= 2
sin
x
2
x
2
,
since
x>
0. So, by L’Hospital’s Rule,
lim
x
→
0
+
2
sin
x
2
x
2
= 2
·
1 = 2
.
b) Evaluate
integraldisplay
2
0
t
1 +
t
4
dt
using any method.
(Hint: Think arctangent)
Answer:
Let
u
=
t
2
. Then
du
= 2
tdt
or
tdt
=
du
2
.
Hence,
integraldisplay
t
1 +
t
4
dt
=
1
2
integraldisplay
du
1 +
u
2
=
1
2
Arctan
u
=
1
2
Arctan (
t
2
)
.
Therefore,
integraldisplay
2
0
t
1 +
t
4
dt
=
1
2
Arctan(
t
2
)
vextendsingle
vextendsingle
vextendsingle
vextendsingle
2
t
=0
=
1
2
Arctan(4)
.
OR
Let
u
=
t
2
. Then
du
= 2
tdt
or
tdt
=
du
2
.
When
t
= 0,
u
= 0 while if
t
= 2 then
u
= 4.
Hence,
integraldisplay
2
0
t
1 +
t
4
dt
=
1
2
integraldisplay
4
0
du
1 +
u
2
dt
=
1
2
Arctan(
u
)
vextendsingle
vextendsingle
vextendsingle
vextendsingle
4
u
=0
=
1
2
Arctan(4)
.
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1
School of Mathematics and Statistics
Carleton University
Math. 1004 H, Winter 2019
TEST 5
SOLUTIONS
Any wireless calculator permitted, 1 or more blank sheets permitted for roughs
Print Name :
Student Number:
Tutorial Section (H1, H2, H3, H4):
PART I: Multiple Choice Questions
(Choose and CIRCLE only ONE answer - No part marks here.)
1.
[3 marks]
Simplify using long division:
3
x
2
+ 2
x
+ 1
(a) 3
x
+ 2,
(b) 3
x
-
1
-
5
x
+ 1
,
(c) 3
x
-
3 +
5
x
+ 1
,
(d) 3
x
-
1 +
5
x
+ 1
.
Answer:
(c)
2.
[3 marks]
Evaluate
integraldisplay
3 sin
2
x
cos
x dx
(a) sin
3
x
+
C
,
(b)
sin
3
x
3
+
C
,
(c) cos
3
x
+
C
,
(d)
cos
3
x
3
+
C
,
Answer:
(a)
3.
[3 marks]
Evaluate
integraldisplay
sec
5
x
tan
x dx
(a)
sec
6
x
6
+
C
-
6,
(b)
tan
3
x
3
+
C
,
(c)
sec
5
x
5
-
1 +
C
,
(d)
sec
3
x
tan
2
x
3
+
C
.
Answer:
(c)
4.
[3 marks]
Find the form of the partial fraction decomposition of
x
2
+ 2
x
2
(
x
2
-
1)(
x
2
+ 1)
:
(a)
A
x
2
+
B
x
+ 1
+
C
x
-
1
+
Dx
+
E
x
2
+ 1
,
(b)
A
x
+
B
x
+ 1
+
C
x
-
1
+
Dx
+
E
x
2
+ 1
,
(c)
A
x
+
B
x
2
+
C
x
+ 1
+
D
x
-
1
+
E
x
2
+ 1
(d)
A
x
+
B
x
2
+
C
x
+ 1
+
D
x
-
1
+
Ex
+
F
x
2
+ 1
,
(e) None of these.
Answer:
(d)
5.
[3 marks]
Let
F
(
x
) =
integraldisplay
tan
4
x
sec
2
x dx
with
F
(
π/
4) = 3. Then
F
(
x
) =
tan
5
x
5
+ 3
(a) TRUE,
(b) FALSE,
Answer:
(b)
PART II
Show all work here and give details.
Answers only are insufficient for full credit.
No additional pages will be accepted
6.
[4+3 marks]
a) Evaluate
I
=
integraldisplay
sin
3
x
cos
2
x dx
Answer:
There are many ways of doing this, for example: sin
3
x
cos
2
x
= sin
2
x
cos
2
x
sin
x
= (1
-
cos
2
x
) cos
2
x
sin
x
which gives
I
=
integraldisplay
(cos
2
x
-
cos
4
x
) sin
x dx
=
-
integraldisplay
(
u
2
-
u
4
)
du
=
-
cos
3
x
3
+
cos
5
x
5
+
C
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2
b) Evaluate
integraldisplay
x
+ 1
(
x
+ 2)(
x
+ 3)
dx
using the method of partial fractions.
Answer:
x
+ 1
(
x
+ 2)(
x
+ 3)
=
2
x
+ 3
-
1
x
+ 2
so
integraldisplay
x
+ 1
(
x
+ 2)(
x
+ 3)
dx
=
integraldisplay
2
x
+ 3
dx
-
integraldisplay
1
x
+ 2
dx
= 2 ln
|
x
+3
|-
ln
|
x
+2
|
+
C
.
7.
[3 + 3 + 2 marks]
Convert and integrate the rational function
x
4
+ 1
(
x
+ 2)(
x
+ 1)
using partial fractions as follows:
a) Use long division to find the remainder
b) Find the partial fraction decomposition of the remainder
c) Integrate the result in (b).
(
NOTE
: An answer alone is insufficient and worth only 1 mark)
Answer:
a) Long division gives
x
4
+ 1
(
x
+ 2)(
x
+ 1)
=
x
2
-
3
x
+ 7
-
15
x
+ 13
(
x
+ 2)(
x
+ 1)
.
b)
15
x
+ 13
(
x
+ 2)(
x
+ 1)
=
-
2
x
+ 1
+
17
x
+ 2
c)
integraldisplay
x
4
+ 1
(
x
+ 2)(
x
+ 1)
dx
=
integraldisplay
(
x
2
-
3
x
+ 7)
dx
+
integraldisplay
2
x
+ 1
dx
-
integraldisplay
17
x
+ 2
dx
=
x
3
3
-
3
x
2
2
+ 7
x
+ 2 ln
|
x
+ 1
| -
17 ln
|
x
+ 2
|
.
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1
School of Mathematics and Statistics
Carleton University
Math. 1004H, Winter 2019
TEST 6
Any calculator permitted, no wireless devices. Blank sheets permitted for roughs (don’t hand in)
Print Name :
Student Number:
Tutorial Section (H1, H4, ...):
PART I: Multiple Choice Questions
(Choose and CIRCLE only ONE answer - No part marks here.)
1.
[3 marks]
Evaluate
integraldisplay
∞
0
2
xe
-
2
x
dx
.
(a) 2,
(b) 1,
(c)
1
4
,
(d)
1
2
Answer:
(d)
2.
[3 marks]
Evaluate
integraldisplay
1
0
x
ln
x dx
.
(a)
-
1
4
,
(b)
1
2
,
(c) 0,
(d)
2
3
Answer:
(a)
3.
[3 marks]
Which one of the following integrals represents the area of the region enclosed by the two curves
y
=
x
2
and
y
=
x
?
(a)
integraldisplay
1
0
(
x
-
x
2
)
2
dx
,
(b)
integraldisplay
1
0
(
x
-
x
2
)
dx
,
(c)
integraldisplay
1
0
(
x
2
-
x
)
dx
,
(d)
integraldisplay
2
0
(
x
-
x
2
)
dx
Answer:
(b)
4.
[3 marks]
Find the area of the region enclosed by the curves
y
=
x
2
and
y
= 1.
(a) 8,
(b)
1
4
,
(c)
4
3
,
(d)
2
3
,
Answer:
(c)
5.
[3 marks]
Find an expression for the volume of the solid of revolution obtained by rotating the region in the first
quadrant enclosed by the curves
y
=
√
x
,
x
= 1 and
y
= 0 about the
x
-axis.
(a)
integraldisplay
1
0
πx dx
,
(b)
integraldisplay
1
0
π
√
x dx
,
(c)
integraldisplay
1
0
πx
2
dx
,
(d)
integraldisplay
1
0
2
πx dx
,
Answer:
(a)
PART II: Show all work here and give details.
No additional pages will be accepted
6.
[5+5 marks]
a) Evaluate the integral
integraldisplay
1
0
x
-
1
/
2
1 +
x
1
/
2
dx
.
Answer:
Let
u
= 1 +
x
1
/
2
. Then 2
du
=
x
-
1
/
2
dx
. When
x
= 0,
u
= 1 while if
x
= 1, then
u
= 2. So,
integraldisplay
1
0
x
-
1
/
2
1 +
x
1
/
2
dx
=
integraldisplay
2
1
2
du
u
= 2 ln 2
.
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2
b) Find an expression for the solid of revolution obtained by rotating the region in the first quadrant bounded by the
curves
y
= 2
x
2
,
y
= 2 and
x
= 0, about the
y
-axis. DO NOT EVALUATE the constants nor the integral.
Answer:
The two curves intersect when
x
= 1 and
y
= 2. Using vertical slices we get
r
out
=
x
+
dx
,
r
in
=
x
and
height= 2
-
2
x
2
. When this slice is rotated about the
y
-axis we get its volume as
π
(
r
2
out
-
r
2
in
)
dx
= 2
π x
(2
-
2
x
2
)
dx
.
Hence the required volume is
integraldisplay
1
0
2
π x
(2
-
2
x
2
)
dx.
Alternately, using horizontal slices
r
out
=
radicalbig
y/
2,
r
in
= 0 and height=
dy
. When this slice is rotated about the
y
-axis
we get its volume as
π
(
r
2
out
-
r
2
in
)
dy
=
π
(
radicalbig
y/
2)
2
dy
. Hence the required volume is also equal to
integraldisplay
2
0
π
2
y dy.
7.
[5 marks]
Evaluate the improper integral
integraldisplay
0
-
1
|
x
|
-
1
/
2
dx
.
(Hint: Remove the absolute value and evaluate the integral using the definition of an improper integral)
Answer:
Since
x <
0,
|
x
|
=
-
x
and so, using the substitution
-
x
=
t
,
dx
=
-
dt
, and the definition of the improper
integral we find that
integraldisplay
0
-
1
|
x
|
-
1
/
2
dx
=
integraldisplay
0
-
1
(
-
x
)
-
1
/
2
dx
=
lim
ε
→
0
-
integraldisplay
ε
-
1
(
-
x
)
-
1
/
2
dx
=
lim
ε
→
0
-
-
integraldisplay
-
ε
1
t
-
1
/
2
dt
=
lim
ε
→
0
-
integraldisplay
1
-
ε
t
-
1
/
2
dt
=
lim
ε
→
0
-
2
t
1
/
2
vextendsingle
vextendsingle
vextendsingle
vextendsingle
1
-
ε
= 2
.
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