On the interval $[0,1]$, the function $x^{25}(1-x)^{75}$ takes its maximum value at the point

On the interval $[0,1]$, the function $x^{25}(1-x)^{75}$ takes its maximum value at the point
  1. $\frac{1}{2}$
  2. 0
  3. $\frac{1}{4}$
  4. $\frac{1}{3}$

Solution

$\begin{aligned} & f(x)=x^{25}(1-x)^{75} \\ & \Rightarrow f^{\prime}(x)=25 x^{24}(1-x)^{75}-x^{25} \cdot 75(1-x)^{74} \\ & =25 \cdot x^{24} \cdot(1-x)^{74}(1-4 x)\end{aligned}$ $\begin{aligned} & \Rightarrow f(x) \text { takes maximum value at } x=\frac{1}{4} \\ & \end{aligned}$

Asked in: MHT CET 2022 (08 Aug Shift 2)

Practice more Applications of Derivatives questions on Aicharya