CPKit
v1.6.1

Vector Dot Product

GeometryEasy

Compute scalar projections and angles between vectors.

Alt+Shift+D

Dot Product Vector Grid (Drag Origin A, U head, or V head)

Origin (A) (0, 0)Vector U (B) (5, 0)Vector V (C) (3, 4)
Vector U:[5, 0]
Vector V:[3, 4]
Dot Product value:15
Angle Between (θ):53.13°

Time Complexity

O(1) direct equation

Space Complexity

O(1) auxiliary
Conceptual Overview

The Vector Dot Product U · V computes the projection scaling of V onto U. It is key for checking orthogonality and calculating segment angles.

Mathematical Formula
U \cdot V = U.x \cdot V.x + U.y \cdot V.y = |U||V|\cos(\theta)
Source: CP-Algorithms geometry reference