Prove that `((sec A-1))/((sec A+1))=((1-cos A))/((1+ cos A))`

Prove that (sec 8A-1)/(sec 4A-1)=(Tan8A)/(Tan2A)

Prove that ( 1+ sec A)/( sec A) =(sin ^(2) A)/( 1-cos A)

intx ((sec 2x-1)/(sec 2x+1))dx=

Prove that (cosec A - sin A ) (sec A -cos A) = ( 1)/( tan A +cot A)

((sin 2A)/(sec A -1))((sec 2A)/(sec 2A+1))=

sec h^(-1) ((1)/(3)) =

((sin2A)/(secA-1))((sec2A)/(sec2A+1))=

Prove that: (1+ cos ""(pi)/(10)) (1+ cos ""(3pi)/(10)) (1+ cos ""(7 pi)/(10)) (1+ cos""(9 pi)/(10))=(1)/(16)