>> diary on
>> l=6

l =

     6

>> a = 2

a =

     2

>> w=200/12

w =

   16.6667

>> E=1300000

E =

     1300000

>> I=98.93

I =

   98.9300

>> x=l/2*(1-a^2/l^2)

x =

    2.6667

>> w*x/(24*E*I*l)*(l^4-2*l^2*x^2+l*x^3-2*a^2*l^2+2*a^2*x^2)

ans =

   1.5999e-06

>> l=72

l =

    72

>> a=24

a =

    24

>> x=l/2*(1-a^2/l^2)

x =

    32

>> w*x/(24*E*I*l)*(l^4-2*l^2*x^2+l*x^3-2*a^2*l^2+2*a^2*x^2)

ans =

    0.0332

>> l/360

ans =

    0.2000

>> 0.0332*12

ans =

    0.3984

>> diary off