Misc 34 - Prove that x17 cos4 x dx = 0 - Class 12 Intgeration - Miscellaneous

part 2 - Misc 34 - Miscellaneous - Serial order wise - Chapter 7 Class 12 Integrals

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Misc 34 Prove that ∫_(−1)^1▒𝑥^17 cos^4⁡𝑥 𝑑𝑥=0 Let 𝑓(𝑥)=∫_(−1)^1▒𝑥^17 cos^4⁡𝑥 𝑑𝑥 ∴ 𝑓(−𝑥)=∫_(−1)^1▒(−𝑥)^17 cos^4⁡(−𝑥) 𝑑𝑥 =∫_(−1)^1▒〖(−1)^17 (𝑥)〗^17 [〖𝑐𝑜𝑠 〗⁡(−𝑥) ]^4 𝑑𝑥 =∫_(−1)^1▒〖−(𝑥)〗^17 [cos⁡𝑥 ]^4 𝑑𝑥 =−∫_(−1)^1▒𝑥^17 cos^4⁡𝑥 𝑑𝑥 Since 𝒇(𝒙)=−𝒇(−𝒙) ∴ I=∫_(−1)^1▒𝑥^17 〖𝑐𝑜𝑠〗^4⁡𝑥 𝑑𝑥 =𝟎

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo