integrate this

IIT JEE 2015 Answers › Calculus questions › integrate this

âˆ«cos⁸x

#Mathematics #Calculus

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6 Answers

62

Lokesh Verma ·2009-11-04 01:55:30

This should not be too much of an issue if you use the same method as used in integrating cos²x
Here you will have to use the same thing 3 times....

can you?

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341

Hari Shankar ·2009-11-04 02:32:30

You could use:

\cos^8 x = \frac{\cos 8 x + 8 \cos 6x + 28 \cos 4x + 56 \cos 2x + 35}{128}

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xYz ·2009-11-04 02:36:31

sir did u obtain this using binomial theorem +demoivre theorem..........

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24

eureka123 ·2009-11-04 03:03:06

use Demovier

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341

Hari Shankar ·2009-11-04 20:00:31

No, start with 4\cos^4 x = (1+\cos 2x)^2 and without much sweat you get that expression

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RAY ·2009-11-04 23:26:25

qustions is wrong :P...ders no dx......hence the function âˆ«cos8x is non-integrateble

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