Find the difference quotient,f(x+h)-f(x)/h, for the function and simplify it.
g(x)=9x2+9x-14

A)18xh+9h+9h^2
B)18x+9
C)18x+9+9h
D)9x+6+18h

what am i suppose to do?

Question

Find the difference quotient,f(x+h)-f(x)/h, for the function and simplify it.
g(x)=9x2+9x-14

A)18xh+9h+9h^2
B)18x+9
C)18x+9+9h
D)9x+6+18h

what am i suppose to do?

perl · Answer

simplify the expression [g( x + h) - g(x)] / h

anonymous · Answer

@perl can u come and help?

anonymous · Answer

@perl i cant wrap my head around the problem, can you explain little more?

campbell_st · Answer

well you are being asked to use 1st principals... 

so 
$$g(x) = 9x^2 + 9x - 14$$

and 

$$g(x+h) = 9(x + h)^2 + 9(x + h) - 14$$

does that make sense?

anonymous · Answer

i think i do

anonymous · Answer

am i suppose to distribute the 9 and get (9x+9h)^2 and 9x+9h - 14 and get as a whole 
18xh^2+9x+9h-14

campbell_st · Answer

no 9(x + h)2 = 9(x^2 + 2xh + h^2) = 9x^2 + 18xh + 9h^2 
     9(x + h) 9x + 9h

campbell_st · Answer

oops and 9(x + h) = 9x + 9h

collect you like terms and simplify

anonymous · Answer

9x^2+18xh+9h^2+9x+9h?

campbell_st · Answer

well 

g(x+h) - g(x) = 9x^2 + 18xh + 9h^2 + 9x + 9h - 14 - 9x^2 +9x + 14
------------   -------------------------------------------------
        h                                                               h

simplify this