Consider this function f(x)=7+4x^2-x^4 (Max,Min,Inflection,etc.) 10pts!

(a) Find the intervals of increase.
Find the intervals of decrease.
(b) Find the local minimum value.
Find the local maximum values.
(c) Find the inflection points.
Find the interval the function is concave up.
Find the intervals the function is concave down.

Thanks in advance!!

Domain is all real. so the interval of increase is taken from the first derivative
a) Inc(-infinity, -2^.5), (0,2^.5)
Dec(-(2^.5),0), (2^.5)
b)local min is at x=0 with a value of 7
local maxes are at x=-(2^.5) with a value of 11
and x=2^.5 with a value of 11
c) + and - (2/3)^.5
Concave up (-(2/3)^.5, to (2/3)^.5)
Concave down on (-infinity , -(2/3)^.5) and (2/3)^.5, to infinity)