f(x)=-3x+1
Using this function, plug everything into the difference quotient formula
[-3(x+h)+1-(-3x+1)]/h Simplify using the distributive property
[-3x-3h+1+3x-1]/h Simplify by combining like terms
-3h/h cancel out the h's
-3
f(x) = 2x2-x-1
Using this function, plug everything into the difference quotient formula
[2(x+h)2-(x+h)-1-(2x2-x-1)]/h FOIL and distribute
[2(x2+2xh+h2)-x-h-1-2x2+x+1]/h Distribute the last set of parenthesis from the FOILed part
[2x2+4xh+2h2-x-h-1-2x2+x+1]/h Simplify by combining like terms
[4xh+2h2-h]/h Factor an h from the numerator
[h(4x+2h-1)]/h cancel out the h's
4x+2h-1