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योगस्थः कुरु कर्माणि सङ्गं त्यक्त्वा धनंजय ।
सिद्ध्यसिद्ध्योः समो भूत्वा समत्वं योग उच्यते ॥२- ४८॥

yogasthaH kuru karmaaNi sa~NgaM tyaktwaa dhanaMjaya ।

siddhyasiddhyoH samo bhootwaa samatwaM yoga uchyate ॥२- ४८॥

Source: Automatic ITRANS Transliteration

O Dhananjaya, perform actions committed to yoga, forsaking attachment,
Having become the same in success or failure. Equanimity is called Yoga.

Source: Milind S. Pandit

Do your duty to the best of your ability, O Arjuna, with your mind attached to the Lord, abandoning (worry and) attachment to the results, and remaining calm in both success and failure. The equanimity of mind is called Karma-yoga.

Source: The Bhagavad-Gita: The Sacred Song

Be steadfast in yoga, O Arjuna. Perform your duty and abandon all attachment to success or failure. Such evenness of mind is called yoga.

Source: Bhagavad Gita As It Is