Table of contents
- 0. Fundamental Concepts of Algebra3h 29m
- 1. Equations and Inequalities3h 27m
- 2. Graphs1h 43m
- 3. Functions & Graphs2h 17m
- 4. Polynomial Functions1h 54m
- 5. Rational Functions1h 23m
- 6. Exponential and Logarithmic Functions2h 28m
- 7. Measuring Angles40m
- 8. Trigonometric Functions on Right Triangles2h 5m
- 9. Unit Circle1h 19m
- 10. Graphing Trigonometric Functions1h 19m
- 11. Inverse Trigonometric Functions and Basic Trig Equations1h 41m
- 12. Trigonometric Identities 2h 34m
- 13. Non-Right Triangles1h 38m
- 14. Vectors2h 25m
- 15. Polar Equations2h 5m
- 16. Parametric Equations1h 6m
- 17. Graphing Complex Numbers1h 7m
- 18. Systems of Equations and Matrices3h 6m
- 19. Conic Sections2h 36m
- 20. Sequences, Series & Induction1h 15m
- 21. Combinatorics and Probability1h 45m
- 22. Limits & Continuity1h 49m
- 23. Intro to Derivatives & Area Under the Curve2h 9m
14. Vectors
Unit Vectors and i & j Notation
Struggling with Precalculus?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
If vector v⃗= 11ȷ^ and vector u⃗= 10ı^−25ȷ^ calculate v⃗+51u⃗ using ı^ & ȷ^ notation.
A
13ı^+14ȷ^
B
2ı^+14ȷ^
C
13ı^−5ȷ^
D
2ı^+6ȷ^

1
Identify the given vectors: \( \mathbf{v} = 11\mathbf{j} \) and \( \mathbf{u} = 10\mathbf{i} - 25\mathbf{j} \).
Calculate \( \frac{1}{5} \mathbf{u} \) by multiplying each component of \( \mathbf{u} \) by \( \frac{1}{5} \). This gives \( \frac{1}{5} \mathbf{u} = \frac{1}{5}(10\mathbf{i} - 25\mathbf{j}) = 2\mathbf{i} - 5\mathbf{j} \).
Add the vectors \( \mathbf{v} \) and \( \frac{1}{5} \mathbf{u} \) together. This means adding their respective components: \( 0\mathbf{i} + 11\mathbf{j} + 2\mathbf{i} - 5\mathbf{j} \).
Combine the \( \mathbf{i} \) components: \( 0\mathbf{i} + 2\mathbf{i} = 2\mathbf{i} \).
Combine the \( \mathbf{j} \) components: \( 11\mathbf{j} - 5\mathbf{j} = 6\mathbf{j} \). The resulting vector is \( 2\mathbf{i} + 6\mathbf{j} \).