by quotient rule:
dy/dx = ( (x-9)^2 (6) - 6x(2)(x-9))/(x-9)^4
= 0 at a horizontal tangent
6(x-9)^2 - 12x(x-9) = 0
6(x-9)[x-9 - 2] = 0
6(x-9)(x-11) = 0
x=9 or x=11 , but x≠9 , there is a vertical asymptote at x=9
x = 11
Determine all values of x, (if any), at which the graph of the function has a horizontal tangent.
y(x) = 6x/(x-9)^2
2 answers
I have these answer choices:
x=9 and x=6
x=-9
x=-9 and x=6
x= 6
The graph has no horizontal tangents.
x=9 and x=6
x=-9
x=-9 and x=6
x= 6
The graph has no horizontal tangents.