Skip to main content
Ch. 4 - Laws of Sines and Cosines; Vectors
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601Non è quello che usi tu?Cambia libro di testo
Capitolo 4, Problema 33

In Exercises 21–38, let u = 2i - 5j, v = -3i + 7j, and w = -i - 6j. Find each specified vector or scalar.
3v - 4w

Guida verificata passo dopo passo
1
Identify the given vectors: \( \mathbf{v} = -3\mathbf{i} + 7\mathbf{j} \) and \( \mathbf{w} = -\mathbf{i} - 6\mathbf{j} \).
Multiply vector \( \mathbf{v} \) by the scalar 3: calculate \( 3\mathbf{v} = 3(-3\mathbf{i} + 7\mathbf{j}) \).
Multiply vector \( \mathbf{w} \) by the scalar 4: calculate \( 4\mathbf{w} = 4(-\mathbf{i} - 6\mathbf{j}) \).
Subtract the vector \( 4\mathbf{w} \) from \( 3\mathbf{v} \): compute \( 3\mathbf{v} - 4\mathbf{w} \) by subtracting corresponding components.
Write the resulting vector in component form \( a\mathbf{i} + b\mathbf{j} \) by combining the \( \mathbf{i} \) and \( \mathbf{j} \) components from the subtraction.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
2m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Vector Representation in Component Form

Vectors in two dimensions can be expressed as components along the i (x-axis) and j (y-axis) unit vectors. For example, u = 2i - 5j means the vector has an x-component of 2 and a y-component of -5. This form allows for straightforward addition, subtraction, and scalar multiplication of vectors.
Video consigliato:
Percorso guidato
03:55
Position Vectors & Component Form

Scalar Multiplication of Vectors

Scalar multiplication involves multiplying each component of a vector by a scalar (a real number). For instance, multiplying vector v by 3 means multiplying both its i and j components by 3, resulting in a new vector scaled in magnitude but with the same direction if the scalar is positive.
Video consigliato:
Percorso guidato
05:05
Multiplying Vectors By Scalars

Vector Addition and Subtraction

Adding or subtracting vectors is done component-wise by adding or subtracting their corresponding i and j components. For example, to find 3v - 4w, first multiply each vector by its scalar, then subtract the resulting components to get the final vector.
Video consigliato:
Percorso guidato
05:29
Adding Vectors Geometrically