Application of DerivativeHard

Question

If f(x) = ln (x - 2)  - 1/x, then

Options

A.f(x) is M.I. for x ∈ (2, ∞)
B.f(x) is M.I. for x ∈ [- 1, 2]
C.f(x) is always concave downwards
D.f-1(x) is M.I. wherever defined

Solution

f(x) = ln(x - 2) - 1/x
f′(x) =
=
As ln(x - 2) is defined when x > 2
⇒ f(x) is M.I. for x ∈ (2, ∞)
⇒ f-1(x) is M.I. wherever defined
Also    f″(x) = < 0
⇒  f(x) is always concave downward

Create a free account to view solution

View Solution Free
Topic: Application of Derivative·Practice all Application of Derivative questions

More Application of Derivative Questions