Evaluate the binomial theorem!
Mathematica 36

InputForm@Expand[(#1 a + #2 b )^#3] &amp;


Usage

InputForm@Expand[(#1 a + #2 b )^#3] &amp;[5, .5, 6]


Result:

15625*a^6 +9375.*a^5*b +2343.75*a^4*b^2 +312.5*a^3*b^3 +23.4375*a^2*b^4 + 0.9375*a*b^5 + 0.015625*b^6