A=∫_0 ^(2α) 2pcos^(−1) (d/(2p))×((Ldβ)/(cos β)) =∫_0 ^(2α) 2(((tan β+(√(tan^2 β−4(atan β−H))))/2))cos^(−1) (L/(l(((tan β+(√(tan^2 β−4(atan β−H))))/2))))×L(dβ/(cos β)) =∫_0 ^(2α) 2(((tan β+(√(tan^2 β−4(atan β−H))))/2))cos^(−1) (((H−(((tan β+(√(tan^2 β−4(atan β−H))))/2))^2 )/(sin β))/( (√((a−b−htan α)^2 +R^2 −h^2 tan^2 (α/2)+((((a−b)tan β)/(1+tan αtan β)))^2 ))(((tan β+(√(tan^2 β−4(atan β−H))))/2))))×(((H−(((tan β+(√(tan^2 β−4(atan β−H))))/2))^2 )/(sin β)))(dβ/(cos β)) =∫_0 ^(2α) 2(((tan β+(√(tan^2 β−4(atan β−H))))/2))cos^(−1) (((H−(((tan β+(√(tan^2 β−4(atan β−H))))/2))^2 )/(sin β))/( (√((a−b−((((a−b)tan β)/(1+tan αtan β)))tan α)^2 +R^2 −((((a−b)tan β)/(1+tan αtan β)))^2 tan^2 (α/2)+((((a−b)tan β)/(1+tan αtan β)))^2 ))(((tan β+(√(tan^2 β−4(atan β−H))))/2))))×(((H−(((tan β+(√(tan^2 β−4(atan β−H))))/2))^2 )/(sin β)))(dβ/(cos β)) =∫_0 ^(2tan^(−1) (R/(a−b))) 2(((tan β+(√(tan^2 β−4(atan β−H))))/2))cos^(−1) ((((H−(((tan β+(√(tan^2 β−4(atan β−H))))/2))^2 )/(sin β))/( (√((a−b−((((a−b)tan β)/(1+((R/(a−b)))tan β)))×((R/(a−b))))^2 +R^2 −((((a−b)tan β)/(1+(R/(a−b))tan β)))^2 tan^2 ((tan^(−1) ((R/(a−b))))/2)+((((a−b)tan β)/(1+((R/(a−b)))tan β)))^2 ))(((tan β+(√(tan^2 β−4(atan β−H))))/2)))))×(((H−(((tan β+(√(tan^2 β−4(atan β−H))))/2))^2 )/(sin β)))(dβ/(cos β))