Question

need help on attachment

Answer 1

come on Dude!

Answer 2

okay you use the quotient rule:
\[F' \frac{g(x)}{h(x)} = \frac{h(x)g'(x)-h'(x)g(x)}{h(x)^2}\]

g(x) = x
g'(x) = 1
h(x) = 4+x
h'(x) = 1
so you get \[\frac{((4+x)(1))-(1)(x)}{(4+x)^2}\]

you can simplify this to:
\[\frac{(4)}{(4+x)^2}\]

Answer 3

oops, i didn't notice that you need second derivative...

ok lets do that again for 4/(x+4)^2

g(x) = 4
g'(x) = 0
h(x) = (4+x)^2
h'(x) = 2(4+x) (chain rule)
so f''(x) will be \[\frac{0-(2)(x+4)(4)}{(x+4)^4}\] which simplifies to
\[\frac{-8}{(x+4)^3}\]

Answer 4

and that's answer number 3 in the attachment

Answer 5

Thanks, for helping me