Diketahui f(×)=2ײ-×, tentukan rumus fungsi f(1-×)

f(x) = 2x²-x
f(1-x) = 2(1-x)²-(1-x)
f(1-x) = 2 (1-2x+x²)-(1-x)
f(1-x) = 2-4x+2x²-1+x
f(1-x) =2x²-3x+1