okay so what f(3) is saying is that x=3. You have to plug three in for x to make the new equation of 2(3)^3-3(3)+1 next you would do pemdas which is parethesis then exponets then multiplication/division then addition/subtraction to get 2*3=6 6^3 is 216 216-3*3 is 207 207+1 is 208 so the answer is f(3)=208