Mathematics
• Involving the second and no higher power of an unknown quantity or variable.

• ‘In 1826 Cauchy, in the context of quadratic forms in n variables, used the term ‘tableau’ for the matrix of coefficients.’
• ‘If f = 0, then the quartic in y is actually a quadratic equation in the variable y 2.’
• ‘Smith also extended Gauss's theorem on real quadratic forms to complex quadratic forms.’
• ‘Find the 2 roots and a continued fraction for a root of these quadratic equations.’
• ‘He was able to use his methods to prove many results in the theory of quadratic forms and number theory.’

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‘Historically, imaginary numbers first came to light when trying to solve cubic equations, rather than quadratics.’
• ‘The sparseness of the quadratics is what is important here.’
• ‘This is certainly possible and the Babylonians' understanding of quadratics adds some weight to the claim.’
• ‘For that matter quadratics aren't all that tough.’
• ‘The thought that quadratics are now seen as ‘high brow’ really does, once again, make me despair.’