Let A be a Banach algebra, and let E be a weak Banach A-bimodule. An approximately intertwining mapping corresponding to a functional equation E(f ) = 0 is a mapping f :A→E with f(0) = 0suchthat  E(f )    ε, and for each a ∈ A the mappings fa(x) = f(ax) − af (x), af(x) = f(xa) −f(x)a, are continuous at a point. In this paper, we show that every approximately intertwining mapping corre- sponding to Cauchy, generalized Jensen or Trif functional equation can be estimated by an intertwining mapping.

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