If `( cos 13^(@)+sin13^(@))/(cos13^(@)-sin13^(@))=tan A`, then A=_________

Prove that : (cos13^@+sin13^@)/(cos13^@-sin13^@) =tan 58^@ .

Prove that:(i) "tan"69^(@)+"tan"66^(@)+1="tan"69^(@) "tan"66^(@) (ii) (cos13^(@)+"sin"13^(@))/(cos13^(@)-"sin"13^(@))="tan"58^(@)

If (cos13^(0)-sin13^(0))/(cos13^(0)+sin13^(0))+(1)/(cot148^(0))=k, then (k^(2))/(16) is equal to "

cos(sin^(-1)(5/13))=

cos(47^@) cos (13^@) - sin (47^@) sin(13^@)= .........

" The value of ((sin17^(@))(cos13^(@))+(cos17^(@))(sin13^(@)))/((cos23^(@))(cos37^(@))-(sin157^(@))(sin37^(@))) is equal to

cos (sin^(-1) . 5/13) =