Question

parmi les figures suivantes, lesquelles sont des polygones non convexes?

Explanation:

Step1: Recall non - convex polygon definition

A non - convex polygon has at least one interior angle greater than 180 degrees or a line segment between two vertices that lies outside the polygon.

Step2: Analyze each figure

For figure A: All interior angles are less than 180 degrees, it is convex.
For figure B: All interior angles are less than 180 degrees, it is convex.
For figure C: All interior angles are less than 180 degrees, it is convex.
For figure D: There is an interior angle greater than 180 degrees (at the "notch" of the arrow - like shape), it is non - convex.
For figure E: There is an interior angle greater than 180 degrees (at the corner of the "L - like" shape), it is non - convex.
For figure F: All interior angles are less than 180 degrees, it is convex.

Answer:

D. The arrow - shaped figure, E. The L - shaped figure