Question 1083949
3(x+h)2-5(x+h)+6-3x^2+5x-6 distributing the minus sign.
3x^2+6xh+h^2-5x-5h+6-2x^2+5x-6
3x^2 disappears, 5x disappears, 6 disappears
=(6xh+h^2-5h)/h
=(6x+h-5)
as h approaches 0, the value approaches 6x-5. 
When h=0, the value is 6x-5.