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Math essentials

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Parallelogram
Triangle
Parallelogram
π΄π‘Ÿπ‘’π‘Ž = π‘β„Ž = π‘Žπ‘ π‘ π‘–π‘›πœƒ
Trapezoid
You should remember this…
a
πœ‹ = 3.1415
𝑒 = 2.7182
2 = 1.414
3 = 1.732
h
πœƒ
1 π‘Ÿπ‘Žπ‘‘ = 1808 /πœ‹ = 57. 38
b
(π‘₯ ± 𝑦)? = π‘₯ ? ± 2π‘₯𝑦 + 𝑦 ?
π‘₯ ? − 𝑦 ? = (π‘₯ + 𝑦)(π‘₯ − 𝑦)
Triangle
1
π΄π‘Ÿπ‘’π‘Ž = π‘β„Ž
2
h
𝑛! = 1 βˆ™ 2 βˆ™ 3 βˆ™ βˆ™βˆ™βˆ™ βˆ™ 𝑛
0! = 1
b
Circle
Trapezoid
1
π΄π‘Ÿπ‘’π‘Ž = π‘Ž + 𝑏 β„Ž
2
a
Quadratic Equation
π‘Žπ‘₯ ? + 𝑏π‘₯ + 𝑐 = 0
Sector
h
π‘₯E,?
Sphere
Circle
π΄π‘Ÿπ‘’π‘Ž = πœ‹π‘Ÿ ?
π‘ƒπ‘’π‘Ÿπ‘–π‘šπ‘’π‘‘π‘’π‘Ÿ = 2πœ‹π‘Ÿ
b
Sector
Cylinder
E
π΄π‘Ÿπ‘’π‘Ž = π‘Ÿ ? πœƒ
?
𝑆 = π‘Ÿπœƒ
πœƒ - in rad.
r
Sphere
4
π‘‰π‘œπ‘™π‘’π‘šπ‘’ = πœ‹π‘Ÿ O
3
Cone
π΄π‘Ÿπ‘’π‘Ž = 4πœ‹π‘Ÿ ?
r
Cone
1
π‘‰π‘œπ‘™π‘’π‘šπ‘’ = πœ‹π‘Ÿ ? β„Ž
3
𝑆 = πœ‹π‘Ÿ π‘Ÿ ? + β„Ž?
(without base)
−𝑏 ± 𝑏 ? − 4π‘Žπ‘
=
2π‘Ž
S
r
πœƒ
r
Cylinder
Pyramid
π‘‰π‘œπ‘™π‘’π‘šπ‘’ = πœ‹π‘Ÿ ? β„Ž
𝑆 = 2πœ‹π‘Ÿβ„Ž
(without circles)
r
h
Pyramid
1
π‘‰π‘œπ‘™π‘’π‘šπ‘’ = π΄β„Ž
3
h
r
h
A
1
TRIGONOMETRIC FUNCTIONS
tan 𝛼 =
sin 𝛼
cos 𝛼
cot 𝛼 =
cos 𝛼
sin 𝛼
1
cos 𝛼
sec 𝛼 =
𝑦 = sin π‘₯
csc 𝛼 =
1
sin 𝛼
sin(−π‘₯) = − sin π‘₯
cos(−π‘₯ ) = cos π‘₯
x
sin π‘₯
cos π‘₯
o
30
1/2
√3/2
o
45
√2/2
√2/2
60
1/2
√3/2
𝑦 = cos π‘₯
tan(−π‘₯ ) = − tan π‘₯
cot(−π‘₯ ) = − cot π‘₯
π‘₯
tan π‘₯ cot π‘₯
o
30
√3/3
√3
o
45
1
1
60
√3
√3/3
𝑦 = tan π‘₯
O
sin π‘₯ = π‘₯ −
𝑦 = cot π‘₯
Y
Z
π‘₯
π‘₯
π‘₯
+ − +β‹―
3! 5! 7!
cos π‘₯ = 1 −
π‘₯? π‘₯\ π‘₯]
+ −
2! 4! 6!
sin α ± β = sin α cos β ± cos α sin β
sin 2𝛼 = 2 sin 𝛼 cos 𝛼
cos α ± β = cos α cos β βˆ“ sin α sin β
cos 2𝛼 = cos ? 𝛼 − sin? 𝛼
Sines
sin? α + cos ? α = 1
Law of Sines
π‘Ž
𝑏
𝑐
=
=
sin 𝛼 sin 𝛽 sin 𝛾
Law of Cosines
𝑐 ? = π‘Ž? + 𝑏 ? − 2π‘Žπ‘ cos 𝛾
b
𝛼
c
𝛽
𝛾
a
complex
Complex Numbers
𝑖 = −1
π‘₯ + 𝑖𝑦 = π‘Ÿ(cos πœƒ + 𝑖 sin πœƒ) = π‘Ÿπ‘’ de
𝑒 df = −1 (Euler’s Formula)
r
y
πœƒ
x
De Moivre’s Theorem (m-real number)
π‘Ÿ cos πœƒ + 𝑖 sin πœƒ
g
= π‘Ÿ g cos π‘šπœƒ + 𝑖 sin π‘šπœƒ
2
f (x)
f (x) =
f (x) = 5 x
f (x) = 2 x
3. The relationship between exponential functions and logarithm functions
EXPONENTIAL & LOGARITHMIC
We FUNCTIONS
can see the relationship between the exponential function f(x) = e
x
and the logarithm
function f(x) = ln x by looking at their graphs.
π‘₯ j π‘₯ k = π‘₯ jlk
(π‘₯ j )k = π‘₯ jk
(π‘₯𝑦)j = π‘₯ j 𝑦 j
q
π‘₯ = π‘₯ E/r
q
q
π‘₯/𝑦 = π‘₯ / q 𝑦
mn
= π‘₯ jpk
π‘₯ = 1/π‘₯ j
q
π‘₯ g = π‘₯ g/r
π‘₯ s = 1 (π‘₯ ≠ 0)
mo
pj
ln π‘₯𝑦 = ln π‘₯ + ln 𝑦
π‘₯
ln = ln π‘₯ − ln 𝑦
𝑦
ln π‘₯ r = 𝑛 ln π‘₯
𝑒
x
f (x) = x
f (x)
ln x axis.
In general, f(x) = (1/a)x = a−x is a reflection of f(x) = ax inf (x)
the=f(x)
x
e
A particularly important example off (x)
an =exponential
function arises when a = e. You might recall
that the number e is approximately equal to 2.718. The function f(x) = ex is often called ‘the’
x
exponential function. Since e > 1 and 1/e < 1, we can sketch the graphs of the exponential
x
−x
x
functions f(x) = e and f(x) = e = (1/e) .
±de
= cos πœƒ ± 𝑖 sin πœƒ
𝑒 de − 𝑒 pde
sin πœƒ =
2𝑖
de
𝑒 + 𝑒 pde
cos πœƒ =
2
f (x)
You can see straight away that the logarithm function is a reflection of the exponential function
in the line represented by f(x) = x. In other words, the axes have been swapped: x becomes
f(x), and f(x) becomes x.
x
−x
f (x) = e
f (x) = e
HYPERBOLIC
Key Point
FUNCTIONS
x f(x) = ln x.
The exponential function f(x) = ex is the inverse of the logarithm function
π‘₯? π‘₯O
𝑒 =1+π‘₯+ + +β‹―
HYPERBOLIC
FUNCTIONS
2! 3! HYPERBOLIC
FUNCTIONS
GRAPHS OF HYPERBOkfC
m
29
FUNCltONS 29
Exercises
1. Sketch the graph of the function f(x) =4a
www.mathcentre.ac.uk
HYPERBOLIC FUNCTIONS
x
GRAPHS
pm
𝑒m − 𝑒
2
sinh x
sinh π‘₯ =
8.49
8.49
y =
y = sinh x
𝑒 +𝑒
8.50 2
axes.
tanh π‘₯ =(a)
cosh π‘₯ =
8.50
y = coshx
y = coshx
8.52
𝑦 = sinh π‘₯
1
77
10
8.53
-1
10
𝑦 -1
= tanh π‘₯
X
/i
8.51
X
7
1
10
0
sinh
8.54
π‘₯±
𝑦 = sinh π‘₯ cosh 𝑦 ± cosh π‘₯ sinh 𝑦
y = csch x
cosh π‘₯ ± 𝑦 = cosh π‘₯ cosh 𝑦 ± sinh π‘₯ sinh 𝑦
0
sinh
y π‘₯
=
Fig. 8-5
tanh x
c mathcentre 2009
⃝
Fig. 8-2
8.53
Fig. 8-3
y = sech x
siny 𝑖π‘₯ = 𝑖 sinh π‘₯ 8.54
cos 𝑖π‘₯ = cosh
π‘₯
sech x
y = csch
8.54
csch x
tan 𝑖π‘₯
= 𝑖 tanh π‘₯y = cot
𝑖π‘₯— 𝑖 coth π‘₯
Y
sinh 𝑖π‘₯ = 𝑖 sin π‘₯
cosh
𝑖π‘₯ = cos π‘₯ Y
X tanh 𝑖π‘₯ = 𝑖 tan π‘₯ coth 𝑖π‘₯ = X
−𝑖 cot π‘₯ \
0
\
0 X
X
0
y = csch x
8.54
Fig. 8-3
Fig. 8-3
-1
Fig. 8-4
Fig. 8-4 Fig. 8-4Y
1
6
1
3
8.51
y = tanh x
𝑦 = coth π‘₯
Fig. 8-3
\
coth(d)π‘₯a ==
(c) a =
Fig. 8-2
8.53
y = sech x y =
y
y
1
𝑦y== cosh
π‘₯
coth x
Fig. 8-2
/i
1
sinh(−π‘₯) = − sinh π‘₯
cosh −π‘₯ = cosh π‘₯
www.mathcentre.ac.uk
9
tanh −π‘₯ = − tanh
π‘₯
coth −π‘₯ = − coth π‘₯
8.52
y x= coth x
y = coth
/i
X
a = 3 (b) a = 6
cosh
π‘₯
Fig. S-l
y = tanh x
Fig. S-l Fig. S-l
8.52
1
(e) a = 6
3
GRAPHS
HYPERBOkfC
8.51
8.49
y OF
= sinh
x
8.50FUNCltONS
y = coshx
y = tanh x
OF HYPERBOkfC
FUNCltONS
2.
Sketch
the
graph
of
the
function
f(x)
=
log
x
for
the following values of a, on the same
a
m
pm
sinh π‘₯
cosh π‘₯
FUNCltONS
8.51
for the following
of a, on 2009
the same axes.
c values
⃝
mathcentre
(a) a = 3 (b) a = 6 (c) a = 1 (d) a =
29
x
x
()
( 21 ) x
f (x) =
NCTIONS
C
1 x
5
L
X0
x
\
L
0
L
X
Fig. 8-6
Fig. 8-5
sinh 2π‘₯ = 2 sinh π‘₯ cosh π‘₯
cosh 2π‘₯ = cosh? π‘₯ + sinh? π‘₯
Fig.
Fig. 8-5
Fig. 8-6
cosh? π‘₯ −
sinh? π‘₯ =
1 FUNCTIONS
iNVERSE
HYPERROLIC
Y
8-6
L
If x = sinhHYPERROLIC
g, then y = sinh-1 xFUNCTIONS
is called the inverse hyperbolic sine of x. Similarly we
iNVERSE
iNVERSE
FUNCTIONS
X otherHYPERROLIC
The inverse hyperbolic functions are multiple-valued
and.
inverse hyperbolic functions.
3
case of inverse trigonometric functions [sec page 171 we restrict ourselves to principal values
they ean be considered as single-valued.
If
x
=
sinh
g,
then
y
=
sinh-1
x the
is called
inverse sine
hyperbolic
sine of we
x. define
Similarly
If x = sinh g, then y = sinh-1 x is called
inverse the
hyperbolic
of x. Similarly
the we define the
TheThe
following
list shows
the principal
values [unless
otherwise
indicated]
of the
h
inverse
hyperbolic
functions
are
multiple-valued
as inverse
in the
other
inverse
hyperbolic
functions.
The
inverse
hyperbolic
functions
are
multiple-valued
and.
as
in
the and.
other inverse hyperbolic functions.
Line
ANALYTIC GEOMETRY
line
y
𝐴π‘₯ + 𝐡𝑦 + 𝐢 = 0,
𝑦 = π‘šπ‘₯ + 𝑏 (m-slope, b- y intercept)
π‘₯ 𝑦
+ =1
π‘Ž 𝑏
Planeb
x
a
Plane
z
𝐴π‘₯ + 𝐡𝑦 + 𝐢𝑧 + 𝐷 = 0
Circle
c
π‘₯ 𝑦 𝑧
+ + =1
π‘Ž 𝑏 𝑐
b
a
y
x
Circle
y
(π‘₯ − π‘₯8 )? + (𝑦 − 𝑦8 )? = 𝑅?
R
(π‘₯π‘œ , π‘¦π‘œ)
Ellipse
x
Ellipse
(π‘₯ − π‘₯8 )?
𝑦 − 𝑦8
+
?
π‘Ž
𝑏?
y
?
=1
2a
("# , %# )
2b
x
Parabola
y
𝑦 − 𝑦8
?
− 4π‘Ž π‘₯ − π‘₯8 = 0
a
Focus
(π‘₯π‘œ , π‘¦π‘œ )
x
Hyperbola
(π‘₯ − π‘₯8 )?
𝑦 − 𝑦8
−
?
π‘Ž
𝑏?
?
=1
(π‘₯8 , 𝑦8 ) – center
2a, 2b –major and minor axes
4
DERIVATIVES
𝑦=𝑓 π‘₯
𝑑𝑦
𝑓 π‘₯ + βˆ†π‘₯ − 𝑓 π‘₯
= lim
𝑑π‘₯ βˆ†m→s
βˆ†π‘₯
; 𝑦 = 𝑓 π‘₯, 𝑦
πœ•π‘“
𝑓 π‘₯ + βˆ†π‘₯, 𝑦 − 𝑓(π‘₯, 𝑦)
= lim
πœ•π‘₯ βˆ†m→s
βˆ†π‘₯
𝑑𝑒
𝑑𝑣
𝑣
− 𝑒( )
𝑑 𝑒
𝑑π‘₯
𝑑π‘₯
=
𝑑π‘₯ 𝑣
𝑣?
𝑑
𝑑𝑣
𝑑𝑒
𝑒𝑣 = 𝑒
+𝑣
𝑑π‘₯
𝑑π‘₯
𝑑π‘₯
𝑑𝑓(𝑒) 𝑑𝑓 𝑑𝑒
=
(π‘β„Žπ‘Žπ‘–π‘› π‘Ÿπ‘’π‘™π‘’)
𝑑π‘₯
𝑑𝑒 𝑑π‘₯
𝑑
sin π‘₯ = cos π‘₯
𝑑π‘₯
𝑑
cos π‘₯ = − sin π‘₯
𝑑π‘₯
𝑑
1
tan π‘₯ =
𝑑π‘₯
cos ? π‘₯
𝑑
1
cot π‘₯ = − ?
𝑑π‘₯
sin π‘₯
𝑑
sinh π‘₯ = cosh π‘₯
𝑑π‘₯
𝑑
cosh π‘₯ = sinh π‘₯
𝑑π‘₯
𝑑
1
tanh π‘₯ =
𝑑π‘₯
cosh? π‘₯
𝑑
1
coth π‘₯ = −
𝑑π‘₯
sinh? π‘₯
Taylor Series
𝑓 π‘₯ = 𝑓 π‘Ž + 𝑓… π‘Ž π‘₯ − π‘Ž +
𝑑
𝑐π‘₯ r = 𝑛𝑐π‘₯ rpE
𝑑π‘₯
𝑑
1 𝑑𝑒
ln 𝑒 =
𝑑π‘₯
𝑒 𝑑π‘₯
𝑑 „
𝑑𝑒
𝑒 = 𝑒„
𝑑π‘₯
𝑑π‘₯
𝑑 „
𝑑𝑒
„
π‘Ž = π‘Ž ln π‘Ž
𝑑π‘₯
𝑑π‘₯
𝑓′′(π‘Ž)(π‘₯ − π‘Ž)? 𝑓′′′(π‘Ž)(π‘₯ − π‘Ž)O
+
+β‹―
2!
3!
INTEGRALS
𝑒 π‘₯ 𝑣′(π‘₯) 𝑑π‘₯ = 𝑒𝑣 − 𝑣 π‘₯ 𝑒… π‘₯ 𝑑π‘₯
Integration by parts:
π‘₯ rlE
𝑛+1
sin π‘₯ = − cos π‘₯
sinh π‘₯ = cosh π‘₯
π‘₯ r 𝑑π‘₯ =
cos π‘₯ = sin π‘₯
cosh π‘₯ = sinh π‘₯
𝑑π‘₯
= ln π‘₯
π‘₯
tan π‘₯ = −ln cos 𝑒
tanh π‘₯ = ln cosh π‘₯
𝑒 m 𝑑π‘₯ = 𝑒 m
cot π‘₯ = ln sin π‘₯
coth π‘₯ = ln sinh π‘₯
ln π‘₯ 𝑑π‘₯ = π‘₯ ln π‘₯ − π‘₯
Mean Value Theorem
k
𝑓 π‘₯ 𝑑π‘₯ = 𝑏 − π‘Ž 𝑓 𝑐 π‘“π‘œπ‘Ÿ π‘Ž < 𝑐 < 𝑏
j
Leibnitz Rule
𝑑
𝑑π‘₯
k(m)
j(m)
𝑑𝑏
π‘‘π‘Ž
𝑓( π‘₯, 𝑑)𝑑𝑑 = 𝑓 π‘₯, 𝑏
− 𝑓 π‘₯, π‘Ž
+
𝑑π‘₯
𝑑π‘₯
k(m)
j(m)
πœ•π‘“(π‘₯, 𝑑)
𝑑𝑑
πœ•π‘₯
5
ORDINARY DIFFERENTIAL EQUATIONS
Linear 1st Order
𝑑𝑦
+𝑃 π‘₯ 𝑦 =𝑅 π‘₯
𝑑π‘₯
πΌπ‘›π‘‘π‘’π‘”π‘Ÿπ‘Žπ‘‘π‘–π‘›π‘” πΉπ‘Žπ‘π‘‘π‘œπ‘Ÿ = 𝑒
𝑑
𝑦(π‘₯)𝑒 •Œm = 𝑅 π‘₯ 𝑒
𝑑π‘₯
𝑦 π‘₯ = 𝑒p
•Œm
𝑅𝑒
•Œm
𝑑π‘₯ + 𝑐
‹Œm
‹Œm
Bernoulli’s Equation
𝑑𝑦
+ 𝑃 π‘₯ 𝑦 = 𝑅(π‘₯)𝑦 r
𝑑π‘₯
𝑦(π‘₯)Epr = (1 − 𝑛)𝑒 p(Epr)
For n=1, ln 𝑦 =
Linear, Homogeneous,
2nd Order
𝑑? 𝑦
𝑑𝑦
+π‘Ž
+ 𝑏𝑦 = 0
?
𝑑π‘₯
𝑑π‘₯
a, b – real constants
•Œm
𝑅 𝑒 (Epr)
•Œm
𝑑π‘₯ + 𝑐
𝑅 − 𝑃 𝑑π‘₯ + 𝑐
π‘šE π‘Žπ‘›π‘‘ π‘š? π‘Žπ‘Ÿπ‘’ π‘Ÿπ‘œπ‘œπ‘‘π‘  π‘œπ‘“ π‘š? + π‘Žπ‘š + 𝑏 = 0
when π‘šE π‘Žπ‘›π‘‘ π‘š? π‘Žπ‘Ÿπ‘’ π‘Ÿπ‘’π‘Žπ‘™
𝑦 π‘₯ = 𝐢E 𝑒 gΕ½ m + 𝐢? 𝑒 g• m
when π‘šE = π‘š? = π‘š π‘Žπ‘›π‘‘ 𝑖𝑠 π‘Ÿπ‘’π‘Žπ‘™
𝑦 π‘₯ = 𝐢E 𝑒 gm + 𝐢? π‘₯𝑒 gm
when π‘šE = 𝑝 + π‘–π‘ž, π‘š? = 𝑝 − π‘–π‘ž
𝑦 π‘₯ = 𝑒 ‹m 𝐢E sin π‘žπ‘₯ + 𝐢? cos π‘žπ‘₯
Linear, nonHomogeneous, 2nd Order
𝑑? 𝑦
𝑑𝑦
+
π‘Ž
+ 𝑏𝑦 = 𝑅(π‘₯)
𝑑π‘₯ ?
𝑑π‘₯
a,b – real constants
Same cases for π‘šE and π‘š? as above
𝑒 gΕ½ m
𝑦 π‘₯ = 𝐢E 𝑒 gΕ½ m + 𝐢? 𝑒 g• m +
π‘šE − π‘š?
𝑦 π‘₯ = 𝐢E 𝑒 gm + 𝐢? π‘₯𝑒 gm + π‘₯𝑒 gm
𝑒 pgΕ½ m 𝑅𝑑π‘₯ +
𝑒 pgm 𝑅𝑑π‘₯ − 𝑒 gm
𝑒 g• m
π‘š? − π‘šE
π‘₯𝑒 pgm 𝑅𝑑π‘₯
𝑦 π‘₯ = 𝑒 ‹m 𝐢E sin π‘žπ‘₯ + 𝐢? cos π‘žπ‘₯
𝑒 ‹m sin π‘žπ‘₯
𝑒 ‹m cos π‘žπ‘₯
+
𝑒 p‹m 𝑅 cos π‘žπ‘₯ 𝑑π‘₯ −
π‘ž
π‘ž
Euler Equation
𝑑? 𝑦
𝑑𝑦
π‘₯ ? ? + π‘Žπ‘₯
+ 𝑏𝑦 = 𝑅(π‘₯)
𝑑π‘₯
𝑑π‘₯
𝑒 pg• m 𝑅𝑑π‘₯
𝑒 p‹m 𝑅 sin π‘žπ‘₯ 𝑑π‘₯
Substitute π‘₯ = 𝑒 ’ then the equation becomes
𝑑? 𝑦
𝑑𝑦
+ (π‘Ž − 1)
+ 𝑏𝑦 = 𝑅(𝑒 ’ )
?
𝑑𝑑
𝑑𝑑
See solutions above for 2nd order equations.
If 𝑅 π‘₯ = 0 use 𝑦 π‘₯ = π‘₯ g and follow Homogeneous 2nd Order solution
6
VECTOR
ANALYSIS
VECTOR
ANALYSIS
VECTOR ANALYSIS
DotProduct
Product
Dot
Dot
Product
|&||'|cos
cosπœƒ + 0 0≤≤πœƒ +≤≤πœ‹ /
𝐀!βˆ™ πβˆ™ #==|𝐴||𝐡|
! βˆ™ # = |&||'|
cos
+ 10 ≤ + ≤ /
? 1++
?1
?
𝐴&== 𝐴m&
0 𝐴&
— 1++𝐴&
˜3
1
1
& = &0 + &1 + &13
@
7
@
7
CrossProduct
Product
Cross
Cross
Product
!×#==𝐴&|𝐡|
|'|sin
sinπœƒ +𝐧7 0 0≤≤πœƒ +≤≤πœ‹ /
𝐀×𝐁
!×# = & |'| sin + 7 0 ≤ + ≤ /
𝐒
𝐣
𝐀
8
8βƒ—
!
=
&
;
+
&
?
+
𝐀×𝐁 = 𝐴0m 𝐴—1 𝐴˜&3 =
8βƒ— = &0 ; + &1 ? + &3 =
!
𝐡 𝐡 𝐡
m
—
+
+
z
z !
8βƒ— = &: ; + &> ? + &< =
88βƒ—
!
&< =
8!βƒ—
&< =
k
j
k
y
j & ?
>
i
&: ; y
&> ?
i
&: ;
88βƒ—
#
8βƒ—
#
88βƒ—
!
8!βƒ—
x x
𝐀×𝐁 = −𝐁×𝐀
𝐀 βˆ™ 𝐁 = 𝐴m 𝐡m + 𝐴— 𝐡— + 𝐴˜ 𝐡˜
˜
Derivative
𝑑𝐹—
𝑑𝐅 𝑑𝐹m
𝑑𝐹˜
=
𝐒+
𝐣+
𝐀
𝑑π‘₯
𝑑π‘₯
𝑑π‘₯
𝑑π‘₯
Del Operator
πœ•
πœ•
πœ•
∇= 𝐒
+𝐣
+𝐀
πœ•π‘₯
πœ•π‘¦
πœ•π‘§
Gradient of a scalar
πœ•πœ™
πœ•πœ™
πœ•πœ™
∇πœ™ =
𝐒+
𝐣+
𝐀
πœ•π‘₯
πœ•π‘¦
πœ•π‘§
Divergent of a Vector
πœ•
πœ•
πœ•
πœ•πΉm πœ•πΉ— πœ•πΉ˜
∇βˆ™π…= 𝐒
+𝐣
+𝐀
βˆ™ 𝐹m 𝐒 + 𝐹— 𝐣 + 𝐹˜ 𝐀 =
+
+
πœ•π‘₯
πœ•π‘¦
πœ•π‘§
πœ•π‘₯
πœ•π‘¦
πœ•π‘§
Curl of a Vector
𝐒
πœ•
πœ•
πœ•
πœ•
∇×𝐅 = 𝐒
+𝐣
+𝐀
× πΉm 𝐒 + 𝐹— 𝐣 + 𝐹˜ 𝐀 =
πœ•π‘₯
πœ•π‘₯
πœ•π‘¦
πœ•π‘§
𝐹m
Laplacian
∇ βˆ™ ∇πœ™ = ∇? πœ™ =
πœ•?πœ™ πœ•?πœ™ πœ•?πœ™
+
+
πœ•π‘₯ ? πœ•π‘¦ ? πœ•π‘§ ?
∇× ∇πœ™ = 0
𝐣
πœ•
πœ•π‘¦
𝐹—
πœ•?𝐅 πœ•?𝐅 πœ•?𝐅
∇ 𝐅= ?+ ?+ ?
πœ•π‘₯
πœ•π‘¦
πœ•π‘§
?
∇ βˆ™ ∇×𝐅 = 0
Μ‚
𝒏
Divergence Theorem
∇ βˆ™ 𝐅 𝑑𝑉 =
V
𝐀
πœ•
πœ•π‘§
𝐹˜
𝐅 βˆ™ 𝑑𝐒
S
C
S
V
S
(𝛁×𝐅) βˆ™ 𝑑𝐒
S
S
dS
V
Stokes Theorem
𝐅 βˆ™ 𝑑𝒓 =
Μ‚
𝒏
dS
S
C
dS
Μ‚
𝒏
dS
Μ‚
𝒏
C
7
COORDINATE SYSTEMS
Cartesian
z
%
$
πœ•
πœ•
πœ•
∇= 𝐒
+𝐣
+𝐀
πœ•π‘₯
πœ•π‘¦
πœ•π‘§
P(x,y,z)
#Μ‚
!Μ‚
∇? Φ =
πœ•?Φ πœ•?Φ πœ•?Φ
+
+
πœ•π‘₯ ? πœ•π‘¦ ? πœ•π‘§ ?
z
y
Po;ar
x
y
x
Cylindrical
̂𝒛
𝒆
z
π‘₯ = π‘Ÿ cos πœƒ
𝑦 = π‘Ÿ sin πœƒ
𝑧=𝑧
Μ‚πœ½
𝒆
𝑃(π‘Ÿ, πœƒ, 𝑧)
̂𝒓
𝒆
Spherical
∇= 𝒆𝒓
∇? Φ =
πœ•
1 πœ•
πœ•
+ π’†πœ½
+ 𝒆𝒛
πœ•π‘Ÿ
π‘Ÿ πœ•πœƒ
πœ•π‘§
z
πœ• ? Φ 1 πœ•Φ 1 πœ• ? Φ πœ• ? Φ
+
+
+
πœ•π‘Ÿ ? π‘Ÿ πœ•π‘Ÿ π‘Ÿ ? πœ•πœƒ ? πœ•π‘§ ?
x
𝜽
y
r
z
!#"
Spherical
π‘₯ = π‘Ÿ sin πœƒ cos πœ™
𝑦 = π‘Ÿ sin πœƒ sin πœ™
𝑧 = π‘Ÿ cos πœƒ
!#$
'
&
∇= 𝒆𝒓
∇? Φ =
πœ•
1 πœ•
1
πœ•
+ π’†πœ½
+ 𝒆𝝓
πœ•π‘Ÿ
π‘Ÿ πœ•πœƒ
π‘Ÿ sin πœƒ πœ•πœ™
!#%
((*, ', &)
r
y
x
1 πœ• ? πœ•Φ
1
πœ•
πœ•Φ
1
πœ•?Φ
π‘Ÿ
+
sin
πœƒ
+
π‘Ÿ ? πœ•π‘Ÿ
πœ•π‘Ÿ
π‘Ÿ ? sin πœƒ πœ•πœƒ
πœ•πœƒ
π‘Ÿ ? 𝑠𝑖𝑛? πœƒ πœ•πœ™ ?
8
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