(Example of a Linear System)
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::<math>\,ay1(t) + by2(t) = a*C*sin(t) + b*C*cos(t) = C\left\{asin(t) + bcos(t)\right\} = C\left\{ax1(t) + bx2(t)\right\}</math>
 
::<math>\,ay1(t) + by2(t) = a*C*sin(t) + b*C*cos(t) = C\left\{asin(t) + bcos(t)\right\} = C\left\{ax1(t) + bx2(t)\right\}</math>
 +
 +
 +
Thus, <math>\,y(t) = Cx(t)</math> is a linear system.

Revision as of 04:45, 9 September 2008

Linearity

A system is said to be linear if it satisfies the properties of scaling and superposition. Thus, the following holds true for all linear systems:

Suppose there are two inputs
$ \,x1(t) $
$ \,x2(t) $
with outputs
$ \,y1(t) = C\left\{x1(t)\right\} $
$ \,y2(t) = C\left\{x2(t)\right\} $
A linear system must satisfy the condition
$ \,ay1(t) + by2(t) = C\left\{ax1(t) + bx2(t)\right\} $

Example of a Linear System

$ \,x1(t) = sin(t) $
$ \,x2(t) = cos(t) $
$ \,y1(t) = C\left\{x1(t)\right\} = C(sin(t)) $
$ \,y2(t) = C\left\{x2(t)\right\} = C(cos(t)) $
$ \,ay1(t) + by2(t) = a*C*sin(t) + b*C*cos(t) = C\left\{asin(t) + bcos(t)\right\} = C\left\{ax1(t) + bx2(t)\right\} $


Thus, $ \,y(t) = Cx(t) $ is a linear system.

Alumni Liaison

Ph.D. on Applied Mathematics in Aug 2007. Involved on applications of image super-resolution to electron microscopy

Francisco Blanco-Silva