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Question : 38 of 160
Marks:
+1,
-0
Solution:
| sin‌x−sin‌3‌x |
| sin2x−cos2x |
=| sin‌x−(3‌sin‌x−4sin3x) |
| −(cos2x−sin2x) |
=| −2‌sin‌x+4sin2x |
| −(cos‌2‌x) |
=| −2‌sin‌x(1−2sin2x) |
| −(cos‌2‌x) |
=2‌sin‌x(OR) Verify by taking x = 30°
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