Valmiki Ramayana Ayodhya Kanda Sarga 34 Shloka 37
Original Shlokaवञ्चना या तु लब्धा मे तां त्वं निस्तर्तुमिच्छसि। अनया वृत्तसादिन्या कैकेय्याऽभिप्रचोदितः।।.2.34.37।।
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त्वम् you, वृत्तसादिन्या one who destroys the tradition of the race, अनया this, कैकेय्या by Kaikeyi, अभिप्रचोदितः having been instigated, या वञ्चना whichever deceit, लब्धा has been experienced, ताम् that one, निस्तर्तुम् to cross over, इच्छसि wish.
Instigated by this Kaikeyi, the destroyer of traditions (of the race) I have been deceived for which you wish to pay.