Summing it up !!!

Algebra Level 3

In the expression : $(1-x)^{10}$

What is the sum of all positive coefficients??

Details & Assumptions

$\bullet$ In expression $(a+b)^{2}$ , on expanding we get $a^2+2ab+b^2$ .Thus, coefficients are $1,2,1$ and sum of coefficients is $4$