MCQ
$\cot1^\circ\cos2^\circ\cos3^\circ\dots\cos180^\circ=?$
- A$-1$
- B$1$
- ✓$0$
- D$\frac12$
✓
Answer
Correct option: C.
$0$
Since $\cos90^\circ=0$
$\cos1^\circ\cos2^\circ\cos3^\circ\dots\cos90^\circ\dots\cos180^\circ=0$
$\cos1^\circ\cos2^\circ\cos3^\circ\dots\cos90^\circ\dots\cos180^\circ=0$
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