Q. tan65°/cot25° = ?


Q. tan65°/cot25° = ?


Soln,


65∘ + 25∘ = 90∘complementary


So, cot25∘ = tan65∘


Now just replace: tan65∘/cot25∘ = tan65∘/tan65∘ = 1


So: tan65∘/​ cot25∘ = tan65∘/tan65∘ ​=1


Ans:1​ 


Note: α + β = 90° , sin α /cos β = 1, tan α /cot β = 1, sec α /cosec β = 1


Final Key Trick


If angles add to 90° and appear as:



  • sin / cos

  • tan / cot

  • sec / cosec


then value = 1