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Question : 8 of 160
Marks:
+1,
-0
Solution:
| (sin‌+i‌cos‌)8 |
| (sin‌−i‌cos‌)8 |
=| i8(cos‌−i‌sin‌)8 |
| (−i)8(cos‌+i‌sin‌)8 |
=| (cos‌−i‌sin‌)8 |
| (cos‌+i‌sin‌)8 |
=+ [∵erθ=cos‌θ+i‌sin‌θ]
=+ [using De-Moivre]
=+| {cos‌π−i‌sin‌π} |
| {cos‌π+i‌sin‌π} |
==+1
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