Cramer’s rule is applicable on the linear equations. So, for better understanding of the chapter, it’s important to understand the fundamentals of it.
Linear equations: It is a first order equation involving two variables; its graph is a straight line in the coordinate system. Whereas, the equation which doesn’t form a straight line is called a nonlinear equation.
Example of a linear equation:
2x –y +z = 0
Example of a nonlinear equation:
3x^{2} + 2y –z = 0
Now, that you are clear with the difference between linear as well as nonlinear equations it’s easy to understand the application of crammer’s rule. Let’s study what crammer’s rule is.
In linear equations, Cramer's Rule is an open method to solve a system of linear equations with numerous equations when the equation has a unique solution. Cramer’s rule checks you from solving the entire system of equations by solving only one variable. Let's use the following system of equations:
3x+y+z=3
x+y+z=0
Cramer’s rule saves your energy and time both in one go. Once familiar with the Cramer’s rule, you need not to solve the whole system to get the desired value. Be it math’s exercises or physics tests Cramer’s rule is all rounder. It adjusts everywhere to prove its unique nature.
Ø You just pick the variable to be solved.
Ø Replace that variable's column of values in the coefficient determinant with the answer-column's values,
Ø Calculate that determinant
Ø Divide it by the coefficient determinant.
Follow four simple steps and learn the Cramer’s rule to avail its benefits at every step.
Ø There is another method to solve systems of equations, involving a quantity called determinants. Every m×m matrix has a unique determinant. The determinant is a single number.
Ø To find the determinant of a 2×2 matrix, multiply the numbers on the downward diagonal and subtract the product of the numbers on the upward diagonal.
Examples:
x + 2y + 3z = 1
-x + 2z = 2
-2y + z = -2
Determinants and Crammer’s for 2 * 2 systems
x- 2y =4
5x+7y =8
For the following system of equations, find the value of z.
2x + y + z = 1
x – y + 4z = 0
x + 2y – 2z = 3
To solve only for z, I first find the coefficient determinant.
Then I form D_{z} by replacing the third column of values with the answer column:
Then I form the quotient and simplify:
Answer: Z = 2
Wasn’t it an easy chapter to understand? Now, it’s your turn. All you ne4ed to do is solve every equation applying the Cramer’s rule and walk parallel with the crowd of your class.
Related Posts
Testimonials
I have a lot of questions that need to be answered. While searching online, I found the site of StudyFAQ and it is all worth it. The tutor is very kind and I’ve got everything I needed. Thank you so much.
Tutor did a great job. The process was very fast and efficient. I didn’t know that there is a quality and reliable tutoring service provider online. I can now start with my assignment.
I was really having a hard time finding an expert who can help me with my topic. Thanks to StudyFAQ.com, I can start working on my assignment now.