Question 1010483
f(x) = x^2 +4x +7
definition of difference quotient
f'(x) = f(x+h) - f(x) / h
f'(x) = (((x+h)^2 +4(x+h) -7) - (x^2+4x-7)) / h
f'(x) = (x^2+2xh+h^2+4x+4h-7 -x^2-4x+7) / h
f'(x) = (2xh+h^2+4h) / h
f'(x) = (2x +h +4) 
limit as h--->0 f'(x) = 2x+4