Sunday 17 March 2013

ALGEBRAIC FUNCTIONS

A set of all X's is called the DOMAIN
A set of all Y's is called the RANGE
FUNCTION is when the X value of each X,Y pair of coordinates is always a different value.  
A sample set of XY pairs of a function      { (5,2) (6,4) (7,8) }
A sample set of XY pairs "Not" a function { (5,2) (5,4) (5,8) }

f(x) = y or in this case f(x) = 2x + 1 since y = 2x + 1
f(DOMAIN independent value) = (RANGE dependent value)


In this example the range y = 2x + 1   
This is a function, so... f(x) = 2x + 1
EXAMPLE 1 when x = - 1:EXAMPLE 2 when x = + 2:
Given;  f(x) = 2x + 1 
When;  x = -1
then;    f(-1) = 2(-1) + 1
so;         f(-1) = - 2 + 1
and;      f(-1) = -1
conclusion;  f(x) = -1 when x = -1
Given;  f(x) = 2x + 1
when;  x = 2
then;   f(2) = 2(2) + 1
so;        f(2) = 4 + 1
and;     f(2) = 5
conclusion;  f(x) = 5 when x = 2

The equation of a straight line can be written in three different forms. Below are three equation forms and proof they are all equal to each other.
y – y1 = m(x - x1)        :: Point slope equation form.
                                    
Where m=slope and y – yand  x - xare points on the line
y = mx + b                :: Slope Intercept form.   
                                
     Where m=slope, b=y interecpt when x=0
Ax + By = C   
            :: Standard form.
Example:
Lets take the straight line that crosses two (x, y) points of (3,2) and (8,4). The equations for this line are shown below.  All three forms of the equation represent the same straight line shown in the graph.
Graph of a straight liney - 2 = 2/5(x-3) :: Point slope form
y = 2/5x + .8     :: Slope intercept form
2x - 5y = - 4      :: Standard form












We now will provide proof that the line shown in the graph can be represented by an equation in three different forms. Since all the equation forms are equal to one another they can be converted from one form to another and still represent the line. Notice also that if we are given two sets of (x,y) points on the line we can calculate the line slope and y intercept. This is all the information we need to fully describe the line in any of the three equation formats.
·         Convert two points (3,2) and (8,4) to point slope equation form.
(y2 - y1) / (x 2 - x1)          :: Find the slope of the line between two points.
(4 - 2) / (8 - 3)                  :: Enter the values of the two points.
2/5                                  :: This is the slope or m of the line.
(y
 - 2) / (x - 3) = 2/5         :: Replace the y= 4 and x 2 = 8 points with y and x.
((y 
-2)/(x -3)) * (x -3) = 2/5 * (x -3) :: Multiply both sides by (x-3)
y - 2 = 2/5x + .8               :: Point slope form 
y - y1 = m(x - x1)
·         Convert the point slope form of the equation to the slope intercept form.
y - 2 = 2/5(x - 3)              :: Point slope form y - y1 = m(x - x1)
y - 2 +2 = 2/5(x - 3) +2     :: Add +2 to each side
y = 2/5*x - 2/5*3 + 2        :: Multiply the term (x-3) by 2/5
y = 2/5*x - 1.2 + 2           :: Now add -1.2 and +2
y = 2/5x - .8                    :: Change the decimal to a fraction
y = 2/5x - 4/5                  :: Slope intercept form
 y = mx + b
·         Convert the slope intercept form to the standard form.
y = 2/5x - 4/5                     :: Slope intercept form y = mx + b 
y * 5 = (2/5x)*5 - (4/5)*5      :: Multiply each side by 5
5y = 2x - 4                         :: Move 2x to the left side and change the sign.
5y - 2x = - 4                       :: Standard form 
Ax + By = C
·         Convert standard form to point slope form.
2x - 5y = - 4                  :: Standard form of Ax + By = C
2x + 4 = 5y                   :: Move the -4 to the left and 5y to the right.
5y = 2x + 4                   :: Reverse the order to get 5y on the left.
5y/5 = (2x + 4)/5            :: Convert the fraction 4/5 to a decimal
y = 2/5x + .8                 :: Point slope form. 
y - y1 = m(x - x1)

·         Given: (x1 , y1) and (x2, y2) representing two points on a line;
use 
(y - y1)/(x - x1) = (y- y1) / (x- x1) to solve for the lines equation in standard form.
·         Given:  (x, y) and m representing one point on the line and the slope of the line;
use 
(y - y1)/(x - x1) = m and solve for y giving the slope intercept equation form.
·       Given: m and b representing the slope of the line and the y intercept;
use 
y = mx + b to give the slope intercept form of the equation.

0 comments:

Post a Comment

PSU Jobs for Freshers

PSU Name Posts/Notice Num Qualification Last Date
IRCON International Ltd. Assistant Officers (HRM) - 1 Post MBA/PG Diploma in HR/IR & Personnel Mgt. Apr 27
Mazagon Dock Various Contractual Vacancies - 649 Posts Specialized Qualification Accordingly Apr 24
SAIL OCT and ACT in Bhilai Steel Plant - 937 Posts ITI/Diploma in Relevat Trade Apr 14 (Extended from Mar 14)
Oil India Medical Officers - 1 Post MD (Paediatrics) Apr 11
Rubber Board 1 Post B.Sc. in Chemistry with computer knowlwdge Apr 9
ONGC Asst. and Junior Asst. Vacancies - 426 Posts Diploma/High School with Relevant Certificates as Required Apr 5
Western Coalfields Mining Sirdar and Surveyor Vacancies- 242 Posts Specialized Qualification Accordingly Apr 5

SSC Jobs for Freshers

Org. Name Posts/Notice Num Qualification Last Date
SSCSR (Southern Region) 5 Posts - Various Vacancies Specialiized Qualification Accordingly Apr 30
SSCKKR 13 Posts - Various Vacancies Specialiized Qualification Accordingly Apr 26
SSCNER 2 Various Vacancies (Scientfic and Preservation Assistants) Mastrs/B.SC Botany according to Post Apr 22
SSC Prasar Bharati Recruitment 2013 - 1238 Programme and Transmission Executives Graduation in any Related Discipline Apr 19
SSC Hindi Translators and Hindi Pradhyapaks Graduate/Masters in Hindi/English Apr 19
SSC Cabinet Secretariat Recruitment 2013 - 279 Group B & C Vacancies Graduation in any Discipline with Specialiized Qualification Accordingly Apr 17
SSC SI in CAPF & Delhi Police, ASI in CISF and IO in NCB Graduation in any Discipline Apr 12
SSCNER (North Eastern Region) 2 Posts - Scientific Assistants Bachelor's in Physics /Geo-Physics/ Geology/ Meteorology/ Hydro-meteorology Apr 8

Exam Dates



Org. Name Posts/Exam Name Test Date(s) Type
SSC SSC Police Vacancies 2013 - SI in Delhi Police & CAPF, ASI in CISF and IO in NCB - Paper 2 Aug 18 Written
SSC Combined Graduate Level Exam 2013 - Tier 2 Exam July 20 & 21, 2013 Written
SSC Cabinet Secretariat Recruitment 2013 - 279 Group B & C Vacancies - Prelims June 17 Written
SSC SSC Police Vacancies 2013 - SI in Delhi Police & CAPF, ASI in CISF and IO in NCB - Paper 1 June 10 Written
SSC Prasar Bharati Recruitment 2013 - 1238 Programme and Transmission Executives June 2 Written
SSC Hindi Translators and Hindi Pradhyapaks June 2 Written
SSC Engineering Assistant and Technicians Recruitment in Prasar Bharati Exam - 2013 May 26, 2013 Written
SSC Junior Engineer (Civil &
Electrical) Exam, 2013
May 19, 2013 Written
SSC Constables(GD) in CAPFs and Rifleman (GD) in Assam Rifles Exam, 2013 May 12, 2013 Written
SSC Combined Graduate Level Exam 2013 - Tier 1 Exam Apr 14 & 21, 2013 Written