Valmiki Ramayana Yuddha Kanda Sarga 109 Shloka 7
Original Shlokaजेतव्यमितिकाकुत्स्थोमर्तव्यमितिरावणः । धृतौस्ववीर्यसर्वस्वंयुद्धेऽदर्शयतांतदा ।।6.109.7।।
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जेतव्यम् victory, इति thus, काकुत्स्थ: Kakuthsa, मर्तव्यम् death, इति this, रावणः Ravana, धृतौ determined, तदा then, युद्धे in battle, स्ववीर्यसर्वस्वम् their total prowess, अदर्शयताम् exhibited
Kakuthsa Rama, sure of his victory and Ravana thinking surely of his death, exhibited their prowess totally in the battle, with determination.