How do you sketch the graph by determining all relative max and min, inflection points, finding intervals of increasing, decreasing and any asymptotes given #f(x)=(x-4)^2/(x^2-4)#?

1 Answer
Feb 7, 2017

Relative maximum #f(1)=-3# and relative minimum f(4)=0. Asymptotes : #uarr x=+-2 darr. POI : (5.034, 0.0500). f darr# : x in (1, 2) and (2, 4)# and #f uarr :, x in (-oo, -2), (-2, 1) and (4, oo) #

Explanation:

I took 30' for this answer. I should have a break. Please make another answer, without attempting to edit my answer. After some time, I would edit my answer, myself.. I have to repeat this because some rush to supply typo omissions of characters like #. I would do it myself. Logical and computational errors can be pointed out in the comment column and not by editing my answer. .

graph{(x-4)^2/(x^2-4) [-30, 30, -15, 15]}

x-intercept ( y = 0) : 4

y-intercept ( x = 0 ) : #-4#

By actual division and resolving into partial fractions,

#y=f = 1+1/(x-2)-9/(x+2)#

As # x to 2 and -2, f to +-oo#

#f'=-1/(x-2)^2+9/(x+2)^2#

#=8((x-1)(x-4))/(x^2-4)^2#

#=0, when x = 1 and 4,

#f darr# intervals:

#<0, x in (1, 2) and (2, 4)# and

#f uarr# intervals :

#>0, x in (-oo, -2), (-2, 1) and (4, oo) #

Local minimum# #f(4)=0#

Local maximum : #f(1)=-3#

#f''=2/(x-2)^3-18/(x+2)^3=0#, when #9^(1/3)(x-2)=(x+2)#, giving

#x=2(9^(1/3)+1)/(9^(1/3)-1)=5.7034, nearly#

#f'''= -6/(x-2)^4+54/(x+2)^4 ne 0, at x = 5.034#, and here y = 0.05,

nearly

So, the POI is at x = 5.034, nearly