You can expand the algebraic expression (x1+2x2+3x3)4 by multiplying 4 to the expression inside the parenthesis. The process is:
4*(x1+2x2+3x3)
= 4*x1 + 4*2x2 + 4*3x3
= 4x1 + 8x2 + 12x3
The final answer is 4x1 + 8x2 + 12x3. I hope it has come to your help.
