2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/73598Let H be a Schrodinger operator on the real line, where the potential is in L^1 and L^2. We define the perturbed Fourier transform F for H and show that F is an isometry from the absolute continuous subspace onto L^2. This property allows us to construct a kernel formula for spectral operators. The main theorem improves the author's previous result for certain short-range potentials.four pages, to appear in Anal. Theo. ApplSpectral TheoryClassical Analysis and ODEs42C15; 35P25text