Difference between revisions of "Quadratic form"

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'''Quadratic form''' is a function expressed as a multivariable equation in [[linear algebra]] that has only combined power of two.  When represented by [[matrices]], it has a geometric significance as a shift or transformation in coordinates.
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'''Quadratic forms''' are multivariable equations in [[linear algebra]] that have no combined power larger than two.  When represented by [[matrices]], they have a geometric significance as a shift or transformation in coordinates.
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[[Category:linear algebra]]
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A quadratic form ''q('''x''')'' can be written as:
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:''q('''x''')'' = '''''x'''''(''A'' '''''x''''')
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where '''''y''''' = ''A'' '''''x''''' is the vector resulting from multiplying a matrix and a vector (a [[linear transformation]]) and '''''x''''' ('''''y''''') is the [[scalar product]] of vectors.
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[[Category:Linear Algebra]]

Latest revision as of 14:35, July 28, 2016

Quadratic form is a function expressed as a multivariable equation in linear algebra that has only combined power of two. When represented by matrices, it has a geometric significance as a shift or transformation in coordinates.

A quadratic form q(x) can be written as:

q(x) = x(A x)

where y = A x is the vector resulting from multiplying a matrix and a vector (a linear transformation) and x (y) is the scalar product of vectors.