Question 20: Find the length of the distance between the two extreme points of the graph of the function y = x3 + 3×2 – 4?

\(\begin{array}{l}

y’ = 3{x^2} + 6x\\

y’ = 0 \Leftrightarrow \left[\begin{array}{l}[\begin{array}{l}

x = 0\\

x = – 2

\end{array} \right.

\end{array}\)

BBT

The coordinates of the two extreme points are: A(- 2,0), B(0;- 4).

The distance between the two extreme points is: \(AB = \sqrt {{2^2} + {4^2}} = 2\sqrt 5 \).

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