What is the second derivative of #f(x) = 6lnx - 5/ x^4 #?
1 Answer
Jan 15, 2016
f''(x)
#= - 6/x^2 - 100/x^6 #
Explanation:
Begin by writing the function as:
f(x) = 6 lnx -
# 5x^-4 # then f'(x) =
#6.(1/x) + 20x^-5 #
# f'(x) = 6/x + 20x^-5 = 6x^-1 +20x^-5 #
#rArr f''(x) = - 6x^-2 - 100x^-6 = - 6/x^2 - 100/x^6 #
