LinkBack URL
About LinkBacksHi I have a pair of questions that are becoming slowly irritating any help would be greatly appreciated.
Determine where y=(x+1)^4 (e^-x) is increasing and decreasing
and
Determine the critical numbers and points of inflection for y= x^2 (e^-2x)
Hi I have a pair of questions that are becoming slowly irritating any help would be greatly appreciated.
Determine where y=(x+1)^4 (e^-x) is increasing and decreasing
and
Determine the critical numbers and points of inflection for y= x^2 (e^-2x)
For the first one
dy/dx = 4(x+1)^3 e^(-x ) -(x+1)^4e^(-x)
= e^(-x)*(x+1)^3[ 3-x]
the zeroes are x =-1 and 3
Use either a graph or test pts to determine sign on intervals (-inf,-1)
(-1,3) and (3,inf)
Remember any exponential is always positve so you can simplify
by considering (x+1)^3[ 3-x] only
In part 2 it works the same except you also have to consider the second derivative as well
  |
