Revision as of 11:34, 11 September 2008 by Cnphilli (Talk)

Homework 2 part C


What is a linear system?

A system is linear if:
1. The output of summing any two inputs togerther then sending the result through a system is equal to any two inputs sent through a system than added together.
2. Multiplying an input then sending it through the system equals the input sent through the system then multiplied by the constant.

proving this...

      First I will sum the inputs before the system
      the system is        y(t) = 5x(t).
            
                           a(t) = 3t
                           b(t) = 4t
                           
                           c(t) = a(t) + b(t)
                           c(t) = 3t + 4t
                           y(t) = 5(3t + 4t) = 35t
If it works backwards it is linear:
                           y1(t) = 5(3t) = 15t
                           y2(t) = 5(4t) = 20t
                           y3(t) = 15t+20t   = 35t
Both approaches yield the same result.  Therefore it is linear.

Alumni Liaison

Abstract algebra continues the conceptual developments of linear algebra, on an even grander scale.

Dr. Paul Garrett