x^3,4*X^1,8*x^1,8

You have:  x³, 4x, 8x, and 8

 

What do you want to do with them?

x^3,4*X^1,8*x^1,8

 

Translation: I think it is Europeans' way of writing:

(x^3.4) * (x^1.8) * (x^1.8). If so, then just add the exponents together: 3.4 + 1.8 + 1.8 =7, so that:

=x^7.