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Determine Whether The Equation Is Linear In x1,x2,x1,x2, And x3x3
According to the book I'm using, the following are linear equations:
x1+5x2−√2x3=1
πx1−√2x2+13x3=713
The book also states:
a linear equation does not involve any products or roots of variables
What am I missing?
The exercise from the book, Elementary Linear Algebra by Howard Anton/ Chris Rorres: