How to Perform Scalar Multiplication
Scalar multiplication means multiplying every entry of a vector or matrix by the same number, called the scalar. For example, 3 × (2, −1) = (6, −3), and 2 × [[1, 4], [0, 3]] = [[2, 8], [0, 6]]. Multiplying a vector by a positive scalar stretches or shrinks it; a negative scalar also reverses […]
How to Use Parallelogram Rule for Vector Addition and Subtraction
TL;DR: Two arrows tugging on the same starting point, where do they end up combined? The parallelogram rule answers that. Draw both vectors from the same starting point, complete the parallelogram by sketching the opposite sides, and the diagonal from your starting point is the sum. For subtraction, flip the second vector around and add […]
