Let I =         ……….(i)

 I = 

=     ……….(ii)

Adding eq. (i) and (ii),

2I = 

= 

 2I = 

= 

= 

 I =  ……….(iii)

 I = 

=      ……….(iv)

Adding eq. (i) and (ii),

2I = 

= 

 I = 

= 

= 

 I = 

= 

= 

 I = I₁ –  ……….(v)

Where I₁ =  …….(vi)

Putting  in eq. (vi),

Limits of integration when  and 

 From eq. (vi),

I₁ = 

= 

= 

 I₁ = 

= 

 I₁ =  [From eq. (iii)]

Putting this value in eq. (v), I = 

 2I = 

 2I – I = 

 I =