MHT CET202527 Apr 2025Evening ShiftMathematicsApplication of DerivativesActual
The Maximum value of ( 1 x )^x is
Options
- Ae ^ e
- Bx^5
- Cx
- D5-x^5
Correct answer
A. e ^ e
Step-by-step solution
Finding the maximum of f(x) = (1/x)^x Rewriting as f(x) = x^ -x and taking the natural logarithm gives y = -x x , where y = f(x) . Differentiate both sides with respect to x , yielding: 1 y dy dx = -( x + 1) via product rule on -x x dy dx = -y( x + 1) Substitute y = x^ -x to obtain the derivative: dy dx = -x^ -x ( x + 1) Setting dy dx = 0 for critical points, and noting x^ -x > 0 for x > 0 , solve: x + 1 = 0 x = -1 x = e⁻¹ The first derivative test confirms a local maximum at x = e⁻¹ : derivative is positive for x