# Misc 17 - Chapter 5 Class 12 Continuity and Differentiability

Last updated at May 29, 2018 by Teachoo

Last updated at May 29, 2018 by Teachoo

Transcript

Misc 17 If = (cos + sin ) and y= (sin cos ), Find 2 2 If = (cos + sin ) & = (sin cos ) We need to find 2 2 First we find = . = . = Calculating / = sin cos Differentiating . . . . = sin cos = sin cos = sin cos = cos cos = cos . cos + cos . = cos cos + sin . = cos cos sin . = cos cos + . sin = 0+ sin = . . sin Hence / = . . sin Calculating / = (cos + sin ) Differentiating . . . . = (cos + sin ) = cos + sin = cos + sin = sin + sin = sin + . sin + sin . = sin + sin + cos . = sin + sin + . c = . . cos Now , = / / = . . sin . . cos = Again Differentiating . . . . = tan 2 2 = tan 2 2 = tan . 2 2 = sec 2 . 2 2 = sec 2 2 2 = sec 2 . . 2 2 = sec 2 . . cos 2 2 = sec 2 . 1 sec 2 2 = sec 3 . Hence = .

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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.