Valmiki Ramayana Kishkindha Kanda Sarga 27 Shloka 37
Original Shlokaसमुन्मूलय शोकं त्वं व्यवसायं स्थिरं कुरु। ततस्सपरिवारं तं निर्मूलं कुरु राक्षसम्।।4.27.37।।
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त्वम् you, शोकम् sorrow, समुन्मूलय may uproot, व्यवसायम् daring, स्थिरं कुरु be firm in resolve, ततः then, सपरिवारम् along with all relatives, तं निर्मूलं him destroy, कुरु you do, राक्षसम् that demon.
'Root out sorrow. Be daring. Be firm in resolve. (Only) then can you destroy the demon and his family.