Group Members Amina Aslam FA18-EPE-007 Momina Munir FA18-EPE-010 Hafsa Maqasad FA18-EPE-043 Memona Nawaz FA18-Epe-044
Definition : Linear algebra is the branch of mathematics concerning linear equations such as: linear maps such as: and their representations in vector spaces and through matrices. Linear algebra is central to almost all areas of mathematics. Linear equation : linear equation is an algebraic equation in which each term has an exponent of one and the graphing of the equation results in a straight line . An example of linear equation is y=mx + b.
System of Linear E quations : A system of linear Equations is just a set of two or more linear equations . In two variables (x and y) , the graph of a system of two equations is a pair of lines in the plane. EXAMPLE : 1) 3 x +2 y =16 2) 4 x+3y =− 2 7x+y=19 8x − 2y=12 A solution of a linear system is an assignment of values to the variables x 1 , x 2 , ..., x n such that each of the equations is satisfied. The set of all possible solutions is called the solution set . A linear system may behave in any one of three possible ways: The system has infinitely many solutions . The system has a single unique solution . The system has no solution
Consistency Consistent Equation A linear or nonlinear system of equations is called consistent if there is at least one set of values for the unknowns that satisfies each equation in the system—that is, when substituted into each of the equations, they make each equation hold true as an identity . EXPAMPLE: 2 = 1, or x 3 + y 3 = 5 x 3 + y 3 = 6 Inconsistent Equation a linear or non linear equation system is called inconsistent if there is no set of values for the unknowns that satisfies all of the equations . EXPAMPLE: X+Y+Z=3 X+Y+Z=4
Criteria For Consistency Linear systems : A linear system is consistent if and only if its coefficient matrix has the same rank as does its augmented matrix . If coefficient matric rank in not equal to agumanted matric than it is in consistent
Applications Of L inear Algebra : Linear Algebra most apparently uses by Electrical engineers. Various electrical circuits solution like Kirchhoff's laws , ohms law.
The Wheatstone Bridge : A simple circuit for the precise measurements of resistors . Invented by Samuel hunter Christy in 1883 , was named after sir chales Wheatstone who found and popularized the arrangement in 1843. Consist of an electrical source and a galvanometer get connects to parallel branches 4 resistors . 3 of which are known. Example: We absorb a circuit that has a 5v power supply with different loops and resistors. SOLUTION :
We start with general equation Where V is = Voltage I=current Rn=Total resistance of the path for the given current in.
Next we want to look at each loop and set up an equation. We can put these equation in an augmented matrix Row reduced this matrix we get From this we can determine what the current through I1, I2 & I3 are .