`(cos^3 21^@+cos^3 39^@)/(cos 21^@+cos 39^@)`

What is the simplified value of (sin^3 21^@+ cos^3 19^@)/(sin 21^@+ cos 19^@)+sin^2 69^@+ cos^2 71^@+1/(sec69^@ cosec71^@) is : (sin^3 21^@+ cos^3 19^@)/(sin 21^@+ cos 19^@)+sin^2 69^@+ cos^2 71^@+1/(sec69^@ cosec71^@) का सरलीकृत मान क्या हैः

(cos^(3)21^(@)+cos^(3)39^(@))/(cos21^(@)+cos39^(@))=

sin 21^(@) cos 9^(@) - cos 84^(@) cos 6^(@)=

(cos ^ (3) 21 ^ (@) + cos ^ (3) 39 ^ (@)) / (cos21 ^ (@) + cos39 ^ (@))

(cos ^ (3) 21 ^ (0) + cos ^ (3) 39 ^ (@)) / (cos21 ^ (@) + cos39 ^ (@)) =

sin21^(@)cos9^(@)-cos84^(@) cos6^(@)=

A =(cos 9^(@) - sin 9^(@))/(cos 9^(@) + sin 9^(@)) , B = (cos 21^(@) + sin 21^(@))/(cos21^(@) -sin21^(@)) and C= tan 20^(@) + tan40^(@) + sqrt(3)tan20^(@) tan40^(@) then descending order is:

( cos^(2) 33^(@) - cos^(2) 57^@)/( sin 21^(@) - cos 21^(@))=

(cos21^(@) -sin21^(@))/(cos21^(@) + sin21^(@)) A) tan21^(@) B) cot66^(@) C) tan42^(@) D) cot42^(@)

The simplified value of/सरलीकृत मान ज्ञात करें: (sin^3 21+cos^3 19)/(sin 21+ cos19) +sin^2 69+cos^2 71+ 1/(sec69. cosec 71)