Equivalence of a Vector Norm

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I have this for my homework and i need help with this question: For a 2D vector, is norm2 > norm1 possible? Characterize all 2D vectors for which the norm2 is equal to the norm1. Explain graphically.

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For $(x,y) \in \mathbb R^2$ we have

$$||(x,y)||_1 =|x|+|y| \ge \sqrt{x^2+y^2}=||(x,y)||_2,$$

since

$(|x|+|y|)^2=x^2+2|x||y|+y^2 \ge x^2+y^2$.

We have the equality

$$||(x,y)||_1 =|x|+|y| = \sqrt{x^2+y^2}=||(x,y)||_2$$

$ \iff$

$(|x|+|y|)^2=x^2+2|x||y|+y^2 = x^2+y^2 \iff xy=0$.