© examsiri.com
Question : 76 of 120
Marks:
+1,
-0
Solution:
Given expression is,
tan{2tan−1−} We know that,
tan(A−B)=| tan‌A−tan‌B |
| 1+tan‌A.tan‌B |
⇒tan{2tan−1−} =| tan(2tan−1)−tan‌ |
| 1+tan(2tan−1)‌tan‌ |
⇒tan{2tan−1−} =| tan(2tan−1)+1 |
| 1−tan(2tan−1) |
⇒tan{2tan−1−} =| tan(2tan−1)+1 |
| 1−tan(2tan−1) |
....(1)
Now, consider
tan(2tan−1)=| 2‌tan(tan−1) |
| 1−tan2(tan−1) |
⇒tan(2tan−1)= ⇒tan(2tan−1)= Hence, equation (1) becomes
⇒tan{2tan−1−}= ⇒tan{2tan−1−}=−
© examsiri.com
Go to Question: