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Question
The value of cos 1° cos 2° cos 3° ..... cos 180° is
Options
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Solution
Here we have to find: `cos 1° cos 2° cos 3°........... cos180°`
`cos 1° cos 2° cos 3°................ cos180°`
`= cos 1° cos 2° cos 3°............. cos 89° cos 90° cos 91° ............. os 180°` ` [since cos 90°=0]`
`= cos 1° cos 2° cos 3°............0xx cos 90° cos180°`
`= cos 1° cos 2° cos 3°........0 xxcos 90°........... cos 180°`
`= 0`
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