The correct option is A 1
Given, tan1∘.tan2∘.tan3∘.....tan44∘.tan45∘.tan46∘....tan89∘
[∵tanθ=cot(90−θ)]
∴tan1∘.tan2∘.tan3∘.....tan44∘.tan45∘.tan46∘.....tan89∘= tan1∘.tan2∘.tan3∘.....tan44∘.tan45∘.cot(90∘−46∘)....cot(90∘−89∘)
⇒tan1∘.tan2∘.tan3∘.....tan44∘ cot44∘....cot2∘ cot1∘
Rearranging the terms,
=tan1∘ cot1∘.tan2∘cot2∘.tan2∘.cot3∘.....tan44∘ cot44∘
Now, we know that tanθ=1cotθ
⇒tanθ×cotθ=1
Thus,tan1∘.cot1∘.tan2∘cot2∘.tan2∘.cot3∘.....tan44∘.cot44∘=1