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Question : 155 of 180
Marks:
+1,
-0
Solution:
We have,
‌[]−1=‌‌‌[]‌[∵[]−1=‌[]]‌‌ Now, ‌[][]−1=[]‌⇒[](‌)‌[]=[]‌⇒‌[| 1−tan2θ | −2‌tan‌θ |
| 2‌tan‌θ | 1−tan2θ |
]=[]‌⇒[| cos‌2‌θ | −sin‌2θ |
| sin‌2θ | cos‌2‌θ |
]=[]‌∴‌‌a=cos‌2‌θ,b=sin‌2θ‌
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