不妨设z > w > 0 (z = ±w时发散,而负号容易提出),进一步可设z = aw,a>1,则∫{0,+∞} sin(zx)sin(wx)/xdx = ∫{0,+∞} sin(awx)sin(wx)/x dx = ∫{0,+∞} sin(ax)sin(x)/x dx.定义含参变量y的广义积分f(y) = ∫{0,+...