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1 Calculus AP U5 – Integration (AP) Name: ________________
1
Big idea Calculus is an entire branch of mathematics. Calculus is built on two major complementary ideas. The first is differential calculus, which is concerned with the instantaneous rate of change. This can be illustrated by the slope of a tangent to a function's graph. The second is integral calculus, which studies the areas under a curve. These two processes act inversely to each other. Calculus allows you to find optimal solutions to mathematical expressions and is used in medicine, engineering, economics, computer science, business, physical sciences, statistics, and many more areas.
Feedback & Assessment of Your Success
Finished
assignment
pages?
Made
corrections?
Summarized
notes in a
journal?
Added your
own
explanations?
How many
extra
practice
questions
did you try
in each
topic?
Tentative TEST date:
______________________
Date Pages Topics Questions to ask the
teacher:
1.5days
2-4 Antiderivatives & Indefinite Integration (AP) Journal #1
3days
5-11 Estimating Areas – Numerical Integration (AP) Journal #2
1.5days 12-14
Sigma Limits of Finite Sums (AP) Journal #3
15-17
Definite Integrals (AP) Journal #4
2days 18-21
FTC & Average Value (AP) Journal #5
3days
22-27 More FTC & MVT for Integrals (AP) Journal #6
3days 28-33
Interpret Integrals (AP) Journal #7
2 Calculus AP U5 – Integration (AP) Name: ________________
2
ASSIGNMENT Antiderivatives & Indefinite Integration (AP)
1. So far, given a function, we know how to find a
rate of change using the _____________________,
but what if all we knew was how a function was
changing with time, and we wanted to find out
about the function itself? ex. you know velocity
function but what to know the _______________
function.
A function F is called an antiderivative of f on
an interval I if )()( xfxF =′ for all x in I
Theorem: If F is an antiderivative of f on an
interval I , then the most general antiderivative of
f on I is
CxF +)(
where C is an arbitrary constant.
2. Graph a possible ( )F x for the given graph of
( )F x′
Explain why there are infinitely many answers:
3. Find the antiderivatives
a) 3
)( xxf =
b) 2
)(−= xxf
c) 132)(8 ++= xxxf
d) 2
1
2sin5)(−
+= xxxf
e) 6
4
1tansec7)(
−+= xxxxf
f) 2
1
38)(
xxxf
−−=
g) If 21
5cos8)(
xxxf
+−=′ , find )(xf
4. Different notation: Find the indefinite integrals
a) 4 dx
b)
23 x dx
c) ( 1)x x dx+
d) 4
34 x dx
x
+
e)
22 1
x x
dxx
+ +
f)
g)
3 Calculus AP U5 – Integration (AP) Name: ________________
3
In each of the graphs below, determine which curve is )(xf , and which curve is the antiderivative ( )F x .
5.
6.
7. A differential equation is an equation explicitly
solved for a derivative of a particular equation.
Solving a differential equation involves finding the
original function from which the derivative came.
The _______________ solution involves +C . The
_________________ solution uses an
____________________________________ to find
the specific value of C.
A separable differential equation is one where it is
possible to separate all the x and y variables.
• Take Leibniz Form: ( )dy
f xdx
′=
• Change to Differentiable Form: ( )dy f x dx′=
• Perform antiderivative or indefinite integration
operation: ( )dy f x dx′=
8. Sometimes, it is difficult or impossible to find the
antiderivative of a function, but we can still gather
info about it graphically.
A direction field, which shows the slope at given
points, can be used to sketch a graph of the
antiderivative of a function.
Ex. If )1(sin)( +⋅=′ xxxf and 1)0( −=f ,
sketch )(xf .
Solve the differential equations.
9. Given 4 3
dyx
dx= + and (1) 6y = , find the
equation for y
10.
If 3
53
)(x
xxxf
+=′ and
3
1)1( =f , find )(xf
4 Calculus AP U5 – Integration (AP) Name: ________________
4
11. If xxxf +=′′ sin)( with 7)0( =f and
2)0( =′f , find )(xf
12.
Find y(x).
13. Suppose the rate of change of concentration of a
vitamin in the bloodstream at time t is given by
te
dt
dc 3.01.0
−−=
If there is initially 1mg of the vitamin in the
bloodstream, then what is the concentration as a
function of time?
14. A ball is thrown upward with a speed of 10 m/s
from a building that is 30m tall. Find a formula
describing the height of the ball above the ground t
seconds later.
5 Calculus AP U5 – Integration (AP) Name: ________________
5
ASSIGNMENT Estimating Areas – Numerical Integration (AP)
1. A scout moves north in the forest for a distance of
50m in 150sec, stops for 30sec, then moves south
80m in 160sec.
a. Sketch a displacement-time graph
b. Sketch a velocity-time graph
c. Find the area under the velocity-time graph.
d. What does the slope of d-t graph represent?
e. What does the area under the v-t graph
represent?
f. What would the slope of v-t graph represent?
g. What would the area under the a-t graph
represent?
2.
a. Find the instantaneous rate of change at t=1.
What does it represent?
b. Find the average acceleration from t=2 to t=6.
c. Find the distance travelled from t=2 to t=6
d. Sketch d-t graph
6 Calculus AP U5 – Integration (AP) Name: ________________
6
Calculus answers two very important questions. The first, how to find the instantaneous rate of change, we answered
with our study of the derivative. We are now ready to answer the second question: how to find the area of irregular
regions.
3. Goal: To find the area of the shaded region R that
lies above the x-axis, below the graph of 2
1y x= − and between the vertical lines x = 0
and x = 1.
Left Riemann Approximation Method: LRAM
0 1 1
1
0
( ) ( ) ( )
( )
n n
n
k
k
L f x x f x x f x x
x f x
−
−
=
= ∆ + ∆ + + ∆
= ∆
�
we divide the interval ],[ ba into n subintervals of
equal width b a
xn
−∆ = and k
x a k x= + ∆
4. Right Riemann Approximation Method: RRAM
1 2
1
( ) ( ) ( )
( )
n n
n
k
k
R f x x f x x f x x
x f x=
= ∆ + ∆ + + ∆
= ∆
�
Mid Riemann Approximation Method: MRAM
1
1
0
( )2
n
k kn
k
x xM x f
−+
=
+= ∆
7 Calculus AP U5 – Integration (AP) Name: ________________
7
5. For continuous functions f ,
Definite integral of f from a to b is
1
( ) lim ( )n
b
ka n
k
f x dx f x x→∞
=
= ∆where the interval ],[ ba is divided
into n subintervals of equal width
then let n → ∞
Notes:
• x is a ______________ variable
( ) ( )b b
a af x dx f t dt=
• b
adxxf )( is a ____________
called ____________________
while
( )f x dx is a ___________
called ____________________
• b
adxxf )( represents
_______ accumulation over an
interval ],[ ba not ________
since area is always positive!
• If you do think of the integral
as area under curve, then keep
the following in mind:
6. Velocity function of a particle moving left/right on
a horizontal line is 3
2( ) cos 1.5V t t t= + on [ ]0,5 .
a) What does negative velocity on [ ]2,4.5
mean for position of a particle?
b) Find the Right Riemann sum using ten
subintervals.
c) The sum you found, what does it
represent?
d) The actual value of the “area under” is
-2.887m what is the % error in your
answer?
8 Calculus AP U5 – Integration (AP) Name: ________________
8
7. The velocity, m/s2, function of a projectile fired straight up into the air is ( ) 160 9.8f t t= − .
a) Use the Left Riemann sum with six subintervals to estimate how far the projectile rises during the
first 3 sec.
b) How close (% error) do the sums come to the actual value of 435.9 m?
8. Use the midpoint rule to find an approximation to
+
2
1
31
1dx
x using n = 4
9. Use the midpoint rule to approximate
−
+
1
2
25dxx using n = 3
9 Calculus AP U5 – Integration (AP) Name: ________________
9
Trapezoidal Rule
)]()(2)...(2)(2)([2
)( 1210 nn
b
a
n xfxfxfxfxfx
Tdxxf ++++∆
=≈ −
where n
abx
−=∆ and
kx a k x= + ∆
Simpson’s Rule
)]()(4)(2)...(4)(2)(4)([3
)( 123210 nnn
b
a
n xfxfxfxfxfxfxfx
Sdxxf ++++++∆
=≈ −−
where n is even and n
abx
−=∆
10. Use the trapezoidal rule to find an approximation
to 2
1
2
dxe x
using 4=n .
11. Use Simpson’s rule to find an approximation to
2
1
2
dxe x
using 4=n .
12.
10 Calculus AP U5 – Integration (AP) Name: ________________
10
13.
a) Assume ( )f x is continuous, approximate 3
0( )f x dx using LRAM and RRAM and TRAP
b) Approximate (1)f ′
14.
a) Assume ( )f x is continuous, approximate 8
1( )f x dx using LRAM and RRAM and TRAP
b) Approximate (7)f ′
11 Calculus AP U5 – Integration (AP) Name: ________________
11
15. So, we now have methods for approximating
definite integrals, but the question still
remains…how good are these approximations???
As an example, let’s consider an integral that we can
evaluate exactly: 4
1
2
1dx
x. The exact value is
32 .
Here are the associated errors:
Error Bounds
If ET and EM are the errors in the Trapezoidal and
Midpoint rules, respectively, then
2
3
12
)(
n
abKET
−≤ 2
3
24
)(
n
abKEM
−≤
Where Kxf ≤)('' for bxa ≤≤
For Simpson’s Rule, 4
5
180
)(
n
abKES
−≤
where K is now such that Kxf ≤)()4(
16.
Suppose we approximate 3
1
1dx
x using Midpoint
Rule with 5=n
a) What is the maximum possible error?
b) If we want a maximum possible error
of 8
10−
, what value of n should we
use?
17.
If we approximate 2
0
cos
π
xdx using Simpson’s
Rule with 4=n , what is the maximum possible
error?
12 Calculus AP U5 – Integration (AP) Name: ________________
12
ASSIGNMENT Sigma Limits of Finite Sums (AP) Review gr11 math:
1. 4 7 10 13___... 52.− − − − −
a) Number of terms
b) Sum
c) Sigma notation
2. 32 16 8 4 ___ ...+ + + + +
a) Term formula
b) Sum formula
c) Sigma notation
Simplify the following sums
3.
4.
5.
6. Definite integral of f from a to b is
1
( ) lim ( )nb
ka n
k
f x dx f x x→∞
=
= ∆
For continuous functions f , where the interval
],[ ba is divided into n subintervals of equal width
b ax
n
−∆ = and
kx a k x= + ∆
Ex. Express 2
1
5lim
cos
n
kk
nk k
xx x
x→∞=
+ ∆
as a
definite integral on
4,0π
.
13 Calculus AP U5 – Integration (AP) Name: ________________
13
7. Areas Under Curve versus Integrals
Cannot simply evaluate the definite integral! Area
is always ______________! So when using area to
find definite integrals, we are responsible for
assigning the regions the correct ___________.
This means you must find where the graph
_________________________________ then split
up our interval, manually making negative regions
positive: ( ) ( )
c b
a c
f x dx f x dx+
If you’re using a calculator just enter:
Note: placement of absolute value matters!
8. Set up two separate integral expressions that
would give the actual area of the region bounded
by the function 2
( ) 4f x x= − and the x-axis on
the interval [1,5]
9.
Find
4
3
1
( 2 )x x dx− using sums. Does the
answer represent area?
10. Find the area under
2)( xxf = between 0=x
and 1=x using sums.
14 Calculus AP U5 – Integration (AP) Name: ________________
14
11.
Find −
−
4
2
)63( dxx using sums
check your answer graphically using geometric
area formulas
12.
Find +
3
1
)25( dxx using geometric area
13.
Find
5
1
3x dx−
− using geometric area
15 Calculus AP U5 – Integration (AP) Name: ________________
15
ASSIGNMENT Definite Integrals (AP)
1. Just like
0
( ) ( )lim
h
f x h f x
h→
+ − was defined to be the
___________________________
the 1
lim ( )n
kn
k
f x x→∞
=
∆ is defined to be the
___________________________.
Definite integral of f from a to b is
1
( ) lim ( )nb
ka n
k
f x dx f x x→∞
=
= ∆
For continuous functions f , divide the interval ],[ ba into n
subintervals of equal width b a
xn
−∆ = and
kx a k x= + ∆
ie. 0 1 2
( ), , , , ( )n
x a x x x b= =…
Integrability of Continuous Functions
Theorem
If a function f is continuous over the
interval [a, b], then the definite integral
( )b
af x dx
exists and f in integrable over [a, b]
Actually the theorem is also true for
f that has at most ______________
many _______________ discontinuities
Integration Properties
If f and g are integrable on given intervals
1. −=a
b
b
adxxfdxxf )()( ,
2. =a
adxxf 0)( ,
3. −=b
aabccdx )( , c is any constant
4. [ ]( ) ( ) ( ) ( )b b b
a a af x g x dx f x dx g x dx± = ±
5. =b
a
b
adxxfcdxxcf )()( , c is any
constant
6. =+c
a
b
a
c
bdxxfdxxfdxxf )()()(
2. Given the following information:
7)(
8
2
= dxxf , 2)(
8
2
−= dxxg , 9)(
10
2
= dxxf
evaluate these definite integrals:
a) =+ dxxgxf
8
2
)](4)(2[
b) =+ dxxg ]5)(6[
8
2
c) = dxxf
10
8
)(
d)
2
8
( )f x dx
−
−
=
3. 4 6
0 4
6 4
0 6
4 4
0 6
( ) 8 and ( ) 2
a . ( ) b. ( )
c. 4 ( ) d. ( )
f x dx f x dx
f x dx f x dx
f x dx f x dx
−
−
= =
= =
− = =
16 Calculus AP U5 – Integration (AP) Name: ________________
16
4.
5.
17 Calculus AP U5 – Integration (AP) Name: ________________
17
6.
7. Suppose we want to approximate the area under
( ) 2f x x= − between 0x = and 6x = .
a) Find an expression for this area as a limit.
b) Do you know how to evaluate this sum?
c) Rewrite as a definite integral on [0, 6], why does this
no longer represent area?
d) Do you know how to find the indefinite integral for
this function?
8. Suppose we want to approximate the area under
xxf sin)( = between 0=x and 2
π=x .
a) Find an expression for this area as a limit.
b) Do you know how to evaluate this sum?
c) Rewrite this limit as a definite integral
d) Do you know how to find the indefinite integral for
this function?
9. For the above questions we need the __________________________________________to connect the concepts c) and d)…Without it
we can learn more tedious sum simplifications or use a finite n to approximate the answer
18 Calculus AP U5 – Integration (AP) Name: ________________
18
ASSIGNMENT FTC & Average Value of a Function (AP)
1. Fundamental Theorem of Calculus (FTC): Suppose
f is continuous on ],[ ba . Define F as:
p1. ( ) ( ) , x
aF x f t dt a x b= ≤ ≤
then F is continuous on [a,b] and differentiable
on (a,b), and ( ) ( ) ( )x
a
dF x f t dt f x
dx′ = =
p2. −=b
aaFbFdxxf )()()( , where F is
any antiderivative of f .
First part states that __________________ of
________________________ gives back the
function. Note: ___________ limit must be x.
Second part helps you to evaluate definite integrals
without _______________________, it also gives
you _____________________________
Idea behind part 2
Proof of part 1
Notation explanation of part 1
19 Calculus AP U5 – Integration (AP) Name: ________________
19
Review indefinite integrals
2.
++−+ dx
xexx
x2
76sin4
3
3. 2
2
17 1 csc
(2 5) 2
xx dx
x
+ + +
−
Practice FTC part 2
4.
( )2
3
12
xdx
−
5. 36
1( 3)
xe dx−
6. 1
2
1
3 5dx
x− −
7. 1
20
2
64 16
dx
x−
8. 2
0(sin 3 1)x dx
π
+
9. 3
2
0
sec 5 x dx
π
10. Does this method for evaluating definite integrals
always work? Consider the following example
dxxdxx
−
−
−
=
1
1
2
1
1
2
1
11.
20 Calculus AP U5 – Integration (AP) Name: ________________
20
12.
−2
1)( dxxf where
≥+
<
=1,
11
1,2
)(x
x
xx
xf
13.
+3
0)1( dxxx
14. Use Sums, what other method(s) would work?
15. Use Geometric Shapes, what other method(s) would work?
− +1
3)23( dxx
16. Use FTC part 2, what other method(s) would work?
17. 3
21
2
1
xdx
x+ see the need for substitution
method to be learned in the next unit
21 Calculus AP U5 – Integration (AP) Name: ________________
21
Find area bounded by: Find area bounded by:
18.
19.
20. Use the symmetry to find the area bounded by x-
axis and the given function on [-1, 1]
21. Find the average value of )sin()( xxf = on [ ]π,0
22.
dxx
xx−
+
−5
5
2
7
1
43 use symmetry too
23. The temperature of a 5m long metal rod is given byxexf 4
)(−= at a distance of x metres from one end
of the rod. What is the average temperature of the
rod?
22 Calculus AP U5 – Integration (AP) Name: ________________
22
ASSIGNMENT More FTC & MVT for Integrals (AP)
1.
2.
3. Find the interval on which the curve
3 2
0( 1)
x
y t t dt= + + is concave up. Justify your
answer.
4.
23 Calculus AP U5 – Integration (AP) Name: ________________
23
Practice FTC part 1
5.
x
dtttdx
d
3
2sin
6.
7. 03
1x
dt dt
dx+
8.
−
173
x tdt
te
t
dx
d
9.
10.
11.
12.
+3
5
21
x
xdtt
dx
d
24 Calculus AP U5 – Integration (AP) Name: ________________
24
13. The Mean Value Theorem for Integrals: If f is
continuous on ],[ ba , then there exists a number
c in ],[ ba such that
))(()( abcfdxxf
b
a
−=
Demonstrate why theorem would break down for
non continuous functions.
14. Find the value of c guaranteed by the MVT for
integrals for 2
( ) 1f x x= + on [-1,2]. Interpret the
result graphically.
15. Find the value of c guaranteed by the MVT for
derivatives for 2
( ) 1f x x= + on [-1,2]. Interpret
the result graphically.
16. Find the value of c guaranteed by the MVT for
integrals for
17. Find the equation of the tangent line to
2
1( ) cos
x
g x tdt= at ( ,2)π
25 Calculus AP U5 – Integration (AP) Name: ________________
25
The Net Change Theorem: The integral of a rate of
change is the net change:
−=′b
aaFbFdxxF )()()(
Or Accumulation:
what I have now = what I started with + what I've accumulated since the start
( ) ( ) ( )b
aF b F a F x dx′= +
24. If water flows from a tank at a rate of
ttr 2100)( −= litres per minute for 500 ≤≤ t ,
find the amount of water that flows from the tank
in the first 10 minutes.
25. During 34 weeks in the 2000-2001 flu season, the
rate of reported influenza per 100,000 people in
Ireland could be approximated by tetI 1049.0
389.3)( =′ , where I is the total number of
people per 100,000 who have contracted influenza
and t is time measured in weeks. Approximately
how many people per 100,000 contracted
influenza during the whole 34 weeks?
26. At the start of Christmas Break, at t = 0 days, a man
weighed 180 pounds. If the man gained weight
during the break at a rate modeled by the function
( ) 10sin8
tW t
π ′ =
pounds per day, what was
the man’s weight (in pounds) at the end of the
break, 14 days later?
27. If ( ) 4cos
6
xf x
π ′ =
and
3(2)f
π=
a) Find ( 2)f − use symmetry
b) Find ( )f x
26 Calculus AP U5 – Integration (AP) Name: ________________
26
Solve for the indicated variable
28.
29.
30. Evaluate
10
2
0
6 x dx−
31. Find the number(s) b such that the average value
of 2
( ) 2 6 3f x x x= + − on the interval [0,b] is
equal to 3.
32. Suppose that
0
( )3 2
xf t
dt xt
+ = Find f(x)
27 Calculus AP U5 – Integration (AP) Name: ________________
27
33.
34. Population is given by ( ) ln(3 1)P t t= + thousand
of insects where t is number of years since Jan
2000.
a) Find average population from t=5 to t=9
b) Find average change in population from
t=5 to t=9
28 Calculus AP U5 – Integration (AP) Name: ________________
28
ASSIGNMENT Interpret the Integral (AP)
1.
The graph represents a person out for a walk. The
person was 2m to the left of an oak tree at t=0 sec.
a) What direction is the person travelling? When
did she turn around?
b) What does the integral represent?
c) Find the position at t=10sec
d) Find the average velocity on [0,10] using both
formulas given in the journal
e) Find average acceleration on [0,10]
2. If )(th′ is the rate of change of a child’s height
measured in inches per year, what does the
integral ′10
0
)( dtth represent, and what are its
units?
3. Population is growing with a rate
100 25dP
tdt
= + people/year where t is time
since 2000 in years.
a) Record an integral to be used to predict
the population in 2010 if in 2000
population was 30 000 people.
b) Can you solve this integral with techniques
we know so far?
4.
Suppose 5.6mg of dye was injected into the
bloodstream.
a) Record an integral that would represent
the area of under this curve. What does it
represent?
b) Find the efficiency with which the dye is
being processed in L/sec.
29 Calculus AP U5 – Integration (AP) Name: ________________
29
5.
30 Calculus AP U5 – Integration (AP) Name: ________________
30
6.
(d) Find g(-4)
31 Calculus AP U5 – Integration (AP) Name: ________________
31
7.
32 Calculus AP U5 – Integration (AP) Name: ________________
32
8.
(d) Sketch the displacement time graph
33 Calculus AP U5 – Integration (AP) Name: ________________
33
9. The average value of homes in a valley is growing
at a rate of 4t + thousand dollars per year
where t represents the number of years since
2005. If the average value of a home in this area
was $90 000 in 2007 determine when the average
value of a home will be $110 000
10. If oil is leaking from a ruptured tanker at a rate of 0.2
( ) 10tf t e= gallons/hr where t is measured in
hours since the tanker was damaged. Evaluate and
explain the meaning of:
a) 5
0( )f t dt
b) 12
0
1( )
12f t dt
11. A particle moves in a straight line so that its
velocity at time t is given by tttv 2)(2 −= m/s.
a) Find the displacement of the particle
during the first 3 seconds.
b) Find the distance travelled by the particle
during the first 3 seconds.
12. WITH CALC The rate at which people enter an amusement park on any
given day is 2
15600( )
24 160E t
t t=
− + people/hr, and the
rate at which people are leaving is 2
9890L( )
38 370t
t t=
− +
where t is measured in hours after midnight. The park is open
from 9am to 11pm.
a) How many people have entered the park by 5pm?
b) How many people are at the park at 5pm?
c) How does the number of people at the park
changing at 5pm?