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 a⃗=20ı^ and vector b⃗=50ȷ^ calculate a⃗−b⃗ using ı^ and ȷ^ notation.
A
−30ȷ^
B
20ı^−50ȷ^
C
30ı^^
D
20ı^+50ȷ^

1
Identify the given vectors: \( \vec{a} = 20\hat{i} \) and \( \vec{b} = 50\hat{j} \).
Understand that \( \vec{a} - \vec{b} \) means subtracting the components of \( \vec{b} \) from \( \vec{a} \).
Since \( \vec{a} = 20\hat{i} \) has no \( \hat{j} \) component, its \( \hat{j} \) component is 0. Similarly, \( \vec{b} = 50\hat{j} \) has no \( \hat{i} \) component, so its \( \hat{i} \) component is 0.
Subtract the components: \( (20\hat{i} + 0\hat{j}) - (0\hat{i} + 50\hat{j}) = (20 - 0)\hat{i} + (0 - 50)\hat{j} \).
Simplify the expression to get the result: \( 20\hat{i} - 50\hat{j} \).