JEE AdvancedHardQuestion 310013
Question
For f(x) = x^x (x > 0), the minimum occurs at:
- Ax = 1/eCorrect
- Bx = e
- Cx = 1
- Dx = 0
Correct answer
x = 1/e
Explanation
f(x) = x^x → ln f = x ln x → f'/f = ln x + 1 → f'(x) = x^x(ln x + 1) = 0 → ln x = −1 → x = 1/e. f'' > 0 at x = 1/e → minimum.