Let \(f,g\in L^1(\mathbb R)\). Let \(A=f^{-1}(\mathbb C-\{0\})\) and \(B=g^{-1}(\mathbb C-\{0\})\). Show that \[ (f*g)^{-1}(\mathbb C-\{0\})\subset A+B \] where \(A+B=\{x+y:x\in A,y\in B\}\).
Question
Math 6210 • Real Analysis
2004 • Question 5
Question
2004 • Question 5
Let \(f,g\in L^1(\mathbb R)\). Let \(A=f^{-1}(\mathbb C-\{0\})\) and \(B=g^{-1}(\mathbb C-\{0\})\). Show that \[ (f*g)^{-1}(\mathbb C-\{0\})\subset A+B \] where \(A+B=\{x+y:x\in A,y\in B\}\).