Remainder Thereom

The remainder theorem says that if we divide f(x) by (x-a) then the remainder will be f(a). In your example, instead of (x-a) you have (2x-1) so in this case a=0.5 (we find a by solving 2x-1=0). Now evaluate your function replacing x with 0.5. So we have 16(0.5^5)-20(0.5^4)+8=0.5-1.25+8=7.25. So the remainder is 7.25. Hope that helps.