# Misc 8 - Chapter 5 Class 12 Continuity and Differentiability

Last updated at Dec. 8, 2016 by Teachoo

Last updated at Dec. 8, 2016 by Teachoo

Transcript

Misc 8 (Method 1) Differentiate 𝑤.𝑟.𝑡. 𝑥 the function, cos (𝑎 cos𝑥+𝑏 sin𝑥), for some constant 𝑎 and 𝑏. Let 𝑦 = cos (𝑎 cos𝑥+𝑏 sin𝑥) Differentiating 𝑤.𝑟.𝑡.𝑥. 𝑑𝑦𝑑𝑥 = 𝑑(cos a cosx+b sinx𝑑𝑥 𝑑𝑦𝑑𝑥 = − sin𝑥 𝑎 cos𝑥+𝑏 sin𝑥 . 𝑑(𝑎 cos𝑥+𝑏 sin𝑥)𝑑𝑥 = − sin𝑥 𝑎 cos𝑥+𝑏 sin𝑥 . 𝑎 . 𝑑 cos𝑥𝑑𝑥+𝑏 . 𝑑 sin𝑥𝑑𝑥 = − sin𝑥 𝑎 cos𝑥+𝑏 sin𝑥 . 𝑎 − sin𝑥+𝑏 cos𝑥 = − sin𝑥 𝑎 cos𝑥+𝑏 sin𝑥 . − 𝑎 sin𝑥+𝑏 cos𝑥 = − 𝐬𝐢𝐧 𝒂 𝒄𝒐𝒔𝒙+𝒃 𝒔𝒊𝒏𝒙 𝒂 𝒔𝒊𝒏𝒙−𝒃 𝒄𝒐𝒔𝒙

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Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 8 years. He provides courses for Maths and Science at Teachoo. You can check his NCERT Solutions from Class 6 to 12.