Revised SAT Math: Manipulating function expressions April 15, 2016 Leave a Comment Try the following SAT math question that deals with manipulating function expressions. If $f(x)=x^2-x-1$, then $f(x+h)-f(x)$ equals $\quad h^2 – h$ $\quad h(2x+h-1)$ $\quad 2xh-x-1$ $\quad 2xh+x-1$ Choice B