UtshovBhagavad Gita 2.48
योगस्थः कुरु कर्माणि सङ्गं त्यक्त्वा धनञ्जय।
सिद्ध्यसिद्ध्योः समो भूत्वा समत्वं योग उच्यते।।2.48।।
Yogasthah kuru karmani sangam tyaktva dhananjaya
Siddhyasiddhyoh samo bhutva samatvam yoga uchyate
Simple meaning, written by AIArjuna, established in yoga, perform actions, giving up attachment. Being equal in success and failure is called yoga.