Math Formulas with Problems, Study notes of Mathematics

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ALGEBRA 1
LOGARITHM
x
bbNNx == log
Properties
1log
log
log
log
loglog
logloglog
loglog)log(
=
=
=
=
+
=
a
b
x
x
xnx
yx
y
x
yxxy
a
b
n
REMAINDER AND FACTOR THEOREMS
Given:
)(
)(
rx
xf
Remainder Theorem: Remainder = f(r)
Factor Theorem: Remainder = zero
QUADRATIC EQUATIONS
A
ACBB
Root
CBxAx
2
4
0
2
2
±
=
=++
Sum of the roots = - B/A
Products of roots = C/A
MIXTURE PROBLEMS
Quantity Analysis: A + B = C
Composition Analysis: Ax + By = Cz
WORK PROBLEMS
Rate of doing work = 1/ time
Rate x time = 1 (for a complete job)
Combined rate = sum of individual rates
Man-hours (is always assumed constant)
2
22
1
11 ..
))(ker(
..
))(ker(
workofquantity
timesWor
workofquantity
timesWor =
ALGEBRA 2
UNIFORM MOTION PROBLEMS
VtS
=
Traveling with the wind or downstream:
21 VVVtotal
+
=
Traveling against the wind or upstream:
21 VVVtotal =
DIGIT AND NUMBER PROBLEMS
+
+
uth 10100 2-digit number
where: h = hundreds digit
t = tens digit
u = units digit
CLOCK PROBLEMS
where: x = distance traveled by the
minute hand in minutes
x/12 = distance traveled by the hour
hand in minutes
PDF created with pdfFactory trial version www.pdffactory.com
pf3
pf4
pf5
pf8
pf9
pfa
pfd
pfe
pff
pf12
pf13
pf14
pf15
pf16
pf17
pf18
pf19
pf1a
pf1b
pf1c
pf1d
pf1e
pf1f
pf20
pf21

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ALGEBRA 1

LOGARITHM

x

b

x = log N → N =b

Properties

log 1

log

log log

log log

log log log

log( ) log log

=

=

=

= − 

= +

a

b

x x

x n x

x y y

x

xy x y

a

b

n

REMAINDER AND FACTOR THEOREMS

Given:

x r

f x

Remainder Theorem: Remainder = f(r)

Factor Theorem: Remainder = zero

QUADRATIC EQUATIONS

A

B B AC Root

Ax Bx C

2

4

0

2

2

− ± −

    • =

Sum of the roots = - B/A

Products of roots = C/A

MIXTURE PROBLEMS

Quantity Analysis: A + B = C

Composition Analysis: Ax + By = Cz

WORK PROBLEMS

Rate of doing work = 1/ time

Rate x time = 1 (for a complete job)

Combined rate = sum of individual rates

Man-hours (is always assumed constant)

2

2 2

1

1 1

..

( ker )( )

..

( ker )( )

quantityof work

Wor s time

quantityofwork

Wor s time

ALGEBRA 2

UNIFORM MOTION PROBLEMS

S = Vt

Traveling with the wind or downstream:

1 2

V V V

total

Traveling against the wind or upstream:

1 2

V V V

total

DIGIT AND NUMBER PROBLEMS

100 h + 10 t+u → 2-digit number

where: h = hundred’s digit

t = ten’s digit

u = unit’s digit

CLOCK PROBLEMS

where: x = distance traveled by the

minute hand in minutes

x/12 = distance traveled by the hour

hand in minutes

PROGRESSION PROBLEMS

a 1 = first term

an = n

th term

am = any term before an

d = common difference

S = sum of all “n” terms

ARITHMETIC PROGRESSION (AP)

  • difference of any 2 no.’s is constant
  • calcu function: LINEAR (LIN)
[ 2 ( 1 ) ]

1

1

2 1 3 2

a n d
n
S
a a
n
S
d a a a a etc
a a n m d

n

n m

GEOMETRIC PROGRESSION (GP)

  • RATIO of any 2 adj, terms is always constant
  • Calcu function: EXPONENTIAL (EXP)

r n
r
a
S
r
r
a r
S
r
r
a r
S
a
a
a
a
r
a a r

n

nm n m

n

1

1

1

2

3

1

2

HARMONIC PROGRESSION (HP)

  • a sequence of number in which their reciprocals

form an AP

  • calcu function: LINEAR (LIN)

Mean – middle term or terms between two terms

in the progression.

COIN PROBLEMS

Penny = 1 centavo coin

Nickel = 5 centavo coin

Dime = 10 centavo coin

Quarter = 25 centavo coin

Half-Dollar = 50 centavo coin

DIOPHANTINE EQUATIONS

If the number of equations is less than the

number of unknowns, then the equations are

called “Diophantine Equations”.

ALGEBRA 3

Fundamental Principle:

“If one event can occur in m different ways, and

after it has occurred in any one of these ways, a

second event can occur in n different ways, and

then the number of ways the two events can

occur in succession is mn different ways”

PERMUTATION

Permutation of n objects taken r at a time

n r
n
nP

r

Permutation of n objects taken n at a time

nP n! n

=

Permutation of n objects with q,r,s, etc. objects

are alike

qr s
n
P =

Permutation of n objects arrange in a circle

P= ( n− 1 )!

n

th term

Common

difference

Sum of ALL

terms

Sum of ALL

terms

Sum of ALL

terms, r >

Sum of ALL

terms, r < 1

n

th term

ratio

Sum of ALL

terms,

r < 1 , n = ∞

PLANE

TRIGONOMETRY

ANGLE, MEASUREMENTS &

CONVERSIONS

1 revolution = 360 degrees

1 revolution = 2π radians

1 revolution = 400 grads

1 revolution = 6400 mils

1 revolution = 6400 gons

Relations between two angles (A & B)

Complementary angles → A + B = 90°
Supplementary angles → A + B = 180°
Explementary angles → A + B = 360°

Angle (θ) Measurement

NULL (^) θ = 0°

ACUTE (^) 0° < θ < 90°

RIGHT θ = 90°

OBTUSE (^) 90° < θ < 180°

STRAIGHT θ =180°

REFLEX (^) 180° < θ < 360°

FULL OR PERIGON (^) θ = 360°

Pentagram – golden triangle (isosceles)

36 °

72 ° 72 °

TRIGONOMETRIC IDENTITIES

A

A A

A

A A

A A A

A A B

A B

A B A B

A B

A B A B

A B A B A B

A B A B A B

A A

A A

A A

2 cot

cot 1 cot 2

1 tan

2 tan tan 2

cos 2 cos sin

sin 2 2 sin cos

cot cot

cot cot 1 cot( )

1 tan tan

tan tan tan( )

cos( ) cos cos sin sin

sin( ) sin cos cos sin

1 tan sec

1 cot csc

sin cos 1

2

2 2

2

2 2

2 2

2

2

=

= −

=

±

± =

± ± =

± =

± = ±

  • =

  • =

  • =

m

m

m

SOLUTIONS TO OBLIQUE TRIANGLES

SINE LAW

C

c

B

b

A

a

sin sin sin

= =

COSINE LAW

a

2

= b

2

+ c

2

  • 2 b c cos A
b

2

= a

2

+ c

2

  • 2 a c cos B
c

2

= a

2

+ b

2

  • 2 a b cos C

AREAS OF TRIANGLES AND

QUADRILATERALS

TRIANGLES

  1. Given the base and height
Area bh
  1. Given two sides and included angle

sin θ

2

1 Area = ab

  1. Given three sides

2

( )( )( )

a b c s

Area s s a s b s c

=

= − − −

  1. Triangle inscribed in a circle

r

abc Area

4

=

  1. Triangle circumscribing a circle

Area = rs

  1. Triangle escribed in a circle

Area =r( s−a )

QUADRILATERALS

  1. Given diagonals and included angle
sin θ

1 2

Area = dd
  1. Given four sides and sum of opposite angles

2

2 2

( )( )( )( ) cos

2

a b c d s

A C B D

Area s a s b s c s d abcd

=

=

=

= − − − − −

θ

θ

  1. Cyclic quadrilateral – is a quadrilateral

inscribed in a circle

4 ( )

( )( )( )

2

( )( )( )( )

Area

ab cd ac bd ad bc r

a b c d s

Area s a s b s c s d

=

=

= − − − −

d d = ac+bd →

1 2 Ptolemy’s Theorem

  1. Quadrilateral circumscribing in a circle

Area = rs

a b c d
s
Area abcd

THEOREMS IN CIRCLES

TRAPEZOID

A (a b) h

PARALLELOGRAM

sin
sin

1 2

A dd
A bh
A ab

RHOMBUS

sin α

2

1 2

A a
A dd ah

SOLIDS WITH PLANE SURFACE

Lateral Area = (No. of Faces) (Area of 1 Face)

Polyhedron – a solid bounded by planes. The bounding

planes are referred to as the faces and the intersections

of the faces are called the edges. The intersections of the

edges are called vertices.

PRISM

V = Bh
A(lateral) = PL
A(surface) = A(lateral) + 2B

where: P = perimeter of the base

L = slant height

B = base area

Truncated Prism

numberof heights
heights
V B

PYRAMID

A A B
A A
V Bh

surface lateral

lateral faces

( ) ( )

( )

Frustum of a Pyramid

A 1 A 2 A 1 A 2
h
V = + +

A 1 = area of the lower base

A 2 = area of the upper base

PRISMATOID

1 2 m

A A A

h

V = + +

Am = area of the middle section

REGULAR POLYHEDRON

a solid bounded by planes whose faces are congruent

regular polygons. There are five regular polyhedrons

namely:

A. Tetrahedron

B. Hexahedron (Cube)

C. Octahedron

D. Dodecahedron

E. Icosahedron

Name

Type ofFACE

No. of FACES

No. of EDGES

No. of

VERTICES

Formulas for

VOLUME

TetrahedronHexahedronOctahedron Dodecahedron

Icosahedron

TriangleSquareTrianglePentagonTriangle

4

6

4

(^68)

(^86)

12 12

12

30

20

20

30

12

3

12

2

x

V

=

3 x

V

=

3

(^23)

x

V

=

3

(^66). 7

x

V

=

3

(^18). 2

x

V

=

Where: x = length of one edge

SOLIDS WITH CURVED SURFACES

CYLINDER

V = Bh = KL
A(lateral) = PkL = 2 π r h
A(surface) = A(lateral) + 2B

Pk = perimeter of right section

K = area of the right section

B = base area

L= slant height

CONE

A rL
V Bh

lateral

( )

FRUSTUM OF A CONE

A R r L

A A AA

h

V

lateral

( )

1 2 1 2

SPHERES AND ITS FAMILIES

SPHERE

2 ( )

3

A r
V r
surface π

SPHERICAL LUNE

is that portion of a spherical surface bounded by the

halves of two great circles

°

=

90

(deg)

2

( )

π r θ

A surface

SPHERICAL ZONE

is that portion of a spherical surface between two parallel

planes. A spherical zone of one base has one bounding

plane tangent to the sphere.

A r h zone

2 π ( )

=

SPHERICAL SEGMENT

is that portion of a sphere bounded by a zone and the

planes of the zone’s bases.

2

r h

h

V = −

( 3 3 )

6

( 3 )

6

2 2 2

2 2

a b h

h V

a h

h V

= + +

= +

π

π

SPHERICAL WEDGE

is that portion of a sphere bounded by a lune and the

planes of the half circles of the lune.

°

=

270

(deg)

3 π r θ

V

STRAIGHT LINES

General Equation

Ax + By + C = 0

Point-slope form

y – y 1 = m(x – x 1 )

Two-point form

( ) 1

2 1

2 1

1

x x

x x

y y

y y −

− =

Slope and y-intercept form

y = mx + b

Intercept form

b

y

a

x

Slope of the line, Ax + By + C = 0

B

A

m =−

Angle between two lines

1 2

(^121)

tan
mm
m m

Note: Angle θ is measured in a counterclockwise

direction. m 2 is the slope of the terminal side while m 1 is

the slope of the initial side.

Distance of point (x 1 ,y 1 ) from the line

Ax + By + C = 0;

2 2

1 1

A B
Ax By C
d

Note: The denominator is given the sign of B

Distance between two parallel lines

2 2

1 2

A B

C C d

Slope relations between parallel lines:

m 1 = m 2

Line 1 → Ax + By + C 1 = 0
Line 2 → Ax + By + C 2 = 0

Slope relations between perpendicular lines:

m 1 m 2 = –

Line 1 → Ax + By + C 1 = 0
Line 2 → Bx – Ay + C 2 = 0

PLANE AREAS BY COORDINATES

1 2 3 1

1 2 3 1

, , ,.... ,

, , ,.... ,

2

1

y y y y y

x x x x x

A

n

n

Note: The points must be arranged in a counter clockwise

order.

LOCUS OF A MOVING POINT

The curve traced by a moving point as it moves in a

plane is called the locus of the point.

SPACE COORDINATE SYSTEM

Length of radius vector r:

2 2 2 r = x + y + z

Distance between two points P 1 (x 1 ,y 1 ,z 1 ) and

P 2 (x 2 ,y 2 ,z 2 )

2 2 1

2 2 1

2 2 1

d = ( x −x) +(y −y) +(z −z)

ANALYTIC

GEOMETRY 2

CONIC SECTIONS

a two-dimensional curve produced by slicing a plane

through a three-dimensional right circular conical surface

Ways of determining a Conic Section

  1. By Cutting Plane
  2. Eccentricity
  3. By Discrimination
  4. By Equation

General Equation of a Conic Section:

Ax

2

+ Cy

2

+ Dx + Ey + F = 0 **

Cutting plane Eccentricity

Circle Parallel to base e → 0

Parabola Parallel to element e = 1.

Ellipse none e < 1.

Hyperbola Parallel to axis e > 1.

Discriminant **Equation****

Circle B

2

- 4AC < 0, A = C A = C

Parabola B

2

- 4AC = 0

A ≠ C

same sign

Ellipse B

2

- 4AC < 0, A ≠ C

Sign of A

opp. of B

Hyperbola B

2

- 4AC > 0 A or C = 0

CIRCLE

A locus of a moving point which moves so that its

distance from a fixed point called the center is constant.

Standard Equation:

(x – h)

2

+ (y – k)

2

= r

2

General Equation:

x

2

+ y

2

+ Dx + Ey + F = 0

Center at (h,k):

A
E
k
A
D
h

Radius of the circle:

A
F
r = h +k −

2 2 2 or r^ D E^4 F 2

(^1 2 ) = + −

PARABOLA

a locus of a moving point which moves so that it’s always

equidistant from a fixed point called focus and a fixed line

called directrix.

where: a = distance from focus to vertex

= distance from directrix to vertex

AXIS HORIZONTAL:

Cy

2

+ Dx + Ey + F = 0

Coordinates of vertex (h,k):

C

E

k

2

= −

substitute k to solve for h

Length of Latus Rectum:

C

D

LR =

Length of latus rectum:

a

b

LR

2 2

=

Eccentricity:

d

a

a

c

e = =

HYPERBOLA

a locus of a moving point which moves so that the

difference of its distances from two fixed points called the

foci is constant and is equal to length of its transverse

axis.

d = distance from center to directrix

a = distance from center to vertex

c = distance from center to focus

STANDARD EQUATIONS

Transverse axis is horizontal

1

( ) ( )

2

2

2

2

=

− −

b

y k

a

x h

Transverse axis is vertical:

2

2

2

2

b
x h
a
y k

GENERAL EQUATION

Ax

2

- Cy

**2

  • Dx + Ey + F = 0**

Coordinates of the center:

C

E

k

A

D

h

If C is negative, then: a

2 = C, b

2 = A

If A is negative, then: a

2 = A, b

2 = C

Equation of Asymptote:

(y – k) = m(x – h)

Transverse axis is horizontal:

a

b m =±

Transverse axis is vertical:

b

a m =±

KEY FORMULAS FOR HYPERBOLA

Length of transverse axis: 2a

Length of conjugate axis: 2b

Distance of focus to center :

2 2

c = a +b

Length of latus rectum:

a

b

LR

2

Eccentricity:

d

a

a

c

e = =

POLAR COORDINATES SYSTEM
x = r cos θ

y = r sin θ

2 2 r = x + y

x

y

tan θ =

SPHERICAL

TRIGONOMETRY

Important propositions

  1. If two angles of a spherical triangle are equal ,

the sides opposite are equal ; and conversely.

  1. If two angels of a spherical triangle are

unequal , the sides opposite are unequal , and

the greater side lies opposite the greater

angle ; and conversely.

  1. The sum of two sides of a spherical triangle is

greater than the third side.

a + b > c
  1. The sum of the sides of a spherical triangle is

less than 360°.

0° < a + b + c < 360°
  1. The sum of the angles of a spherical triangle is

greater that 180° and less than 540°.

180° < A + B + C < 540°
  1. The sum of any two angles of a spherical

triangle is less than 180° plus the third angle.

A + B < 180° + C

SOLUTION TO RIGHT TRIANGLES

NAPIER CIRCLE

Sometimes called Neper’s circle or Neper’s pentagon, is

a mnemonic aid to easily find all relations between the

angles and sides in a right spherical triangle.

Napier’s Rules

  1. The sine of any middle part is equal to the

product of the cosines of the opposite parts.

Co-op
  1. The sine of any middle part is equal to the

product of the tangent of the adjacent parts.

Tan-ad

Important Rules:

  1. In a right spherical triangle and oblique angle

and the side opposite are of the same quadrant.

  1. When the hypotenuse of a right spherical

triangle is less than 90°, the two legs are of the

same quadrant and conversely.

  1. When the hypotenuse of a right spherical

triangle is greater than 90°, one leg is of the first

quadrant and the other of the second and

conversely.

QUADRANTAL TRIANGLE

is a spherical triangle having a side equal to 90°.

SOLUTION TO OBLIQUE TRIANGLES

Law of Sines:

C
c
B
b
A
a
sin
sin
sin
sin
sin
sin

Law of Cosines for sides:

c a b a b C
b a c a c B
a b c b c A
cos cos cos sin sin cos
cos cos cos sin sin cos
cos cos cos sin sin cos

Law of Cosines for angles:

C A B A B c
B A C A C b
A B C B C a
cos cos cos sin sin cos
cos cos cos sin sin cos
cos cos cos sin sin cos

dx

du

u u

h u

dx

d

dx

du

u u

h u

dx

d

dx

du

u

u

dx

d

dx

du

u

u

dx

d

dx

du

u

u

dx

d

dx

du

u

u

dx

d

dx

du hu hu u

dx

d

dx

du hu hu u

dx

d

dx

du u hu

dx

d

dx

du u hu

dx

d

dx

du u u

dx

d

dx

du u u

dx

d

dx

du

u u

u

dx

d

dx

du

u u

u

dx

d

dx

du

u

u

dx

d

dx

du

u

u

dx

d

dx

du

u

u

dx

d

2

1

2

1

2

1

2

1

2

1

2

1

2

2

2

1

2

1

2

1

2

1

2

1

1

1 (csc )

1

1 (sec )

1

1 (sinh )

1

1 (tanh )

1

1 (cosh )

1

1 (sinh )

(csc ) csc coth

(sec ) sec tanh

(coth ) csc

(tanh ) sec

(cosh ) sinh

(sinh ) cosh

1

1 (csc )

1

1 (sec )

1

1 (cot )

1

1 (tan )

1

1 (cos )

=

=

=

=−

=−

=−

=

=

=

=

=

− DIFFERENTIAL

CALCULUS

LIMITS

Indeterminate Forms

L’Hospital’s Rule

g x
f x
Lim
g x
f x
Lim
g x
f x
Lim

x →a x→a x→a

Shortcuts

Input equation in the calculator

TIP 1: if x → 1, substitute x = 0.

TIP 2: if x →, substitute x = 999999

TIP 3: if Trigonometric, convert to RADIANS then

do tips 1 & 2

MAXIMA AND MINIMA

Slope (pt.) Y’ Y” Concavity

MAX (^0) (-) dec down

MIN (^0) (+) inc up

INFLECTION (^) - No change (^) -

HIGHER DERIVATIVES

n

th derivative of x

n

( x ) n!

dx

d

n

n

n

n

th derivative of xe

n

n X

n

n

xe x n e

dx

d

TIME RATE

the rate of change of the variable with respect to time

dt

dx

= increasing rate

dt

dx

= decreasing rate

APPROXIMATION AND ERRORS

If “dx” is the error in the measurement of a quantity x,

then “dx/x” is called the RELATIVE ERROR.

RADIUS OF CURVATURE

[ 1 ( ') ]

2

3 2

y
y
R

INTEGRAL

CALCULUS 1

u udu u C

u udu u C

udu u C

udu u C

udu u C

udu u C

edu e C

C a

a a du

u C u

du

C n n

u u du

f u gu du f udu gudu

adu au C

du u C

u u

u u

n n

=− +

= +

=− +

= +

= +

=− +

= +

= +

= +

=

  • = +

= +

= +

csc cot csc

sec tan sec

csc cot

sec tan

cos sin

sin cos

ln

ln

..............( 1 ) 1

[ ( ) ( )] ( ) ( )

2

2

1

= −

= + > −

= + < −

=− +

= +

= +

= +

= +

=− +

=− +

=− +

= +

= +

= +

+ 

  

 = −

= +

= +

= +

= − +

= + +

= +

= +

udv uv vdu

C u a a

u

a u a

du

C u a a

u

a u a

du

C u

a

u u a a

du

C a

u

u a

du

C a

u

u a

du

udu u C

udu u C

hu udu hu C

hu udu hu C

hudu u C

hudu u C

udu u C

udu u C

C a

u

au u

du

C a

u

u u a a

du

C a

u

a u a

du

C a

u

a u

du

udu u u C

udu u u C

udu u C

udu u C

coth .......... ....

1

tanh ..............

1

sinh

1

cosh

sinh

coth lnsinh

tanh lncosh

csc coth csc

sec tanh sec

csc coth

sec tanh

cosh sinh

sinh cosh

cos 1

2

sec

1

tan

1

sin

csc lncsc cot

sec lnsec tan

cot lnsin

tan lnsec

1 2 2

1 2 2

1

2 2

1

2 2

1

2 2

2

2

1

2

1

2 2

1 2 2

1

2 2

INTEGRAL

CALCULUS 2

TIP 1: Problems will usually be of this nature:

  • “Find the area bounded by”
  • “Find the area revolved around..”

TIP 2: Integrate only when the shape is IRREGULAR,

otherwise use the prescribed formulas

VOLUME OF SOLIDS BY REVOLUTION

Circular Disk Method

2

1

2

x

x

V π R dx

Cylindrical Shell Method

=

2

1

2

y

y

V π RL dy

Circular Ring Method

= −

2

1

( )

2 2

x

x

V π R r dx

PROPOSITIONS OF PAPPUS

First Proposition: If a plane arc is revolved about a

coplanar axis not crossing the arc, the area of the surface

generated is equal to the product of the length of the arc

and the circumference of the circle described by the

centroid of the arc.

= •

= •

A dS r

A S r

π

π

2

2

Second Proposition: If a plane area is revolved

about a coplanar axis not crossing the area, the volume

generated is equal to the product of the area and the

circumference of the circle described by the centroid of

the area.

= •

= •

V dA r

V A r

π

π

2

2

CENTROIDS OF VOLUMES

  • = •

2

1

x

x

V x dV x

  • = •

2

1

y

y

V y dV y

WORK BY INTEGRATION

Work = force × distance

∫ ∫

2

1

2

1

y

y

x

x

W Fdx Fdy; where F = k x

Work done on spring

1

2

2

W = k x −x

k = spring constant

x 1 = initial value of elongation

x 2 = final value of elongation

Work done in pumping liquid out of the

container at its top

Work = (density)(volume)(distance)
Force = (density)(volume) = ρv

Specific Weight:

Volume

Weight

γwater = 9.81 kN/m

2 SI

γwater = 45 lbf/ft

2 cgs

Density:

Volume

mass

ρwater = 1000 kg/m

3 SI

ρwater = 62.4 lb/ft

3 cgs

ρsubs = (substance) (ρwater)

1 ton = 2000lb

MOMENT OF INERTIA

Moment of Inertia about the x- axis:

=

2

1

2

x

x

x

I y dA

Moment of Inertia about the y- axis:

=

2

1

2

y

y

y

I x dA

Parallel Axis Theorem

The moment of inertia of an area with respect to any

coplanar line equals the moment of inertia of the area

with respect to the parallel centroidal line plus the area

times the square of the distance between the lines.

2

I Ix Ad

x o

Moment of Inertia for Common Geometric

Figures

Square

3

bh
I

x

12

3 bh Ixo =

Triangle

3

bh
I x =

36

3 bh Ixo =

Circle

4

4 r I xo

π

Half-Circle

4

r

I

x

Quarter-Circle

4

r
I

x

Ellipse

4

3 ab I x

π

4

3 ab I y

π

FLUID PRESSURE

F wh dA

F whA γ hA

F = force exerted by the fluid on one side of

the area

h = distance of the c.g. to the surface of liquid

w = specific weight of the liquid (γ)

A = vertical plane area

Specific Weight:

Volume

Weight

γwater = 9.81 kN/m

2 SI

γwater = 45 lbf/ft

2 cgs