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Graduate · Graduate Mathematics

Functional analysis

96 problems in this skill, each with a solver-verified answer key. Answers are checked the moment you submit — with a hint if you want one and a worked solution afterwards.

What the problems look like

A few statements from this skill. Answers, hints and worked solutions live in the practice session.

  1. Warm-up

    In R2\mathbb{R}^2 with the Euclidean inner product, let x=(2,5)x = (2, 5) and y=(5,2)y = (5, 2). The Cauchy–Schwarz inequality states ⟨x,y⟩2≤∥x∥2 ∥y∥2\langle x, y \rangle^2 \le \lVert x \rVert^2 \, \lVert y \rVert^2. Compute the value of the right-hand side ∥x∥2 ∥y∥2\lVert x \rVert^2 \, \lVert y \rVert^2.

  2. Warm-up

    In R2\mathbb{R}^2 with the Euclidean inner product, let x=(3,5)x = (3, 5) and y=(4,5)y = (4, 5). The Cauchy–Schwarz inequality states ⟨x,y⟩2≤∥x∥2 ∥y∥2\langle x, y \rangle^2 \le \lVert x \rVert^2 \, \lVert y \rVert^2. Compute the value of the right-hand side ∥x∥2 ∥y∥2\lVert x \rVert^2 \, \lVert y \rVert^2.

  3. Warm-up

    In R2\mathbb{R}^2 with the Euclidean inner product, let x=(1,5)x = (1, 5) and y=(1,4)y = (1, 4). The Cauchy–Schwarz inequality states ⟨x,y⟩2≤∥x∥2 ∥y∥2\langle x, y \rangle^2 \le \lVert x \rVert^2 \, \lVert y \rVert^2. Compute the value of the right-hand side ∥x∥2 ∥y∥2\lVert x \rVert^2 \, \lVert y \rVert^2.

Problems shown under their original terms: Generated (template, solver-computed).

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