© examsiri.com
Question : 23 of 160
Marks:
+1,
-0
Solution:
We have,
‌‌| sin‌1∘+sin‌2∘+...+sin‌89∘ |
| 2(cos‌1∘+cos‌2∘+...+cos‌44∘)+1 |
‌=‌| (sin‌1∘+sin‌89∘)+(sin‌2∘+sin‌88∘)+...+(sin‌44∘+sin‌46∘)+sin‌45∘ |
| 2(cos‌1∘+cos‌2∘+...+cos‌44∘)+1 |
‌=‌| 2sin‌‌cos‌+2sin‌‌cos‌+...+2sin‌‌cos‌+ |
| 2(cos‌1∘+cos‌2∘+...+cos‌44∘)+1 |
‌=‌| √2(cos‌44∘+cos‌42∘+...+cos‌2∘+cos‌1∘)+ |
| 2(cos‌1∘+cos‌2∘+...+cos‌44∘)+1 |
Let
x=cos‌1∘+cos‌2∘+...+cos‌44∘=‌=‌=‌
© examsiri.com
Go to Question: