hallo
1/(a+b) * (a/b)7/2 * b3 * (b/a)1/2 + (a2 - ab)/(a2-b2) =
1/(a+b) * a7/2/b7/2 * b3 * b1/2/a1/2 + a(a - b)/(a + b)(a - b) =
1/(a+b) * a7/2/a1/2 * b3 * b1/2/b7/2 + a/(a + b) =
1/(a+b) * a7/2-1/2 * b3+1/2-7/2 + a/(a + b) =
1(/a+b) * a3 * b0 + a/(a + b) =
a3/(a+b) + a/(a + b) = (a3+a)/(a+b)