Valmiki Ramayana Yuddha Kanda Sarga 32 Shloka 39
Original Shlokaसतुसर्वंसमर्थ्यैवमन्त्रिभिःकृत्यमात्मनः । सभांप्रविश्यविदधेविदित्वारामविक्रमम् ।।6.32.39।।
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सः that he, मन्त्रिभिः and ministers, आत्मनः himself, सर्वम् all about (Rama's prowess), कृत्यम् the task to be carried out, समर्थ्यैव thinking carefully, सभाम् to the assembly, प्रविश्य entered, रामविक्रमम् Rama's prowess, विदित्वा having known, विदधे to do so.
Having known all about Rama's prowess, Ravana and ministers entered the assembly to think carefully about the task to be carried out and how to do it.