In mathematics, Clarkson's inequalities, named after James A. Clarkson, are results in the theory of L<sup>p</sup> spaces. They give bounds for the L<sup>p</sup>-norms of the sum and difference of two measurable functions in L<sup>p</sup> in terms of the L<sup>p</sup>-norms of those functions individually.
Let (X, ã, μ) be a measure space; let f, g : X â R be measurable functions in L<sup>p</sup>. Then, for 2 ⤠p < +âÂÂ,
For 1 < p < 2,
where
i.e., q = p â (p − 1).