the inverse of a function is exactly as light as the original function is dark (and the other way around).
ðɪ ɪnvˈɜːs əvə fˈʌŋkʃən ɪz ɛɡzˈæktli æz lˈaɪt æz ðɪ ɚɹˈɪdʒɪnəl fˈʌŋkʃən ɪz dˈɑːɹk ænd ðɪ ˈʌðɚ wˈeɪ ɚɹˈaʊnd.