Flashcards · Maths · Vectors, Constructions and Loci
Column Vectors and Vector Arithmetic
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What is a vector?
A quantity with a size and a direction, such as a movement.
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What does the top number of a column vector show?
The horizontal move, right if positive.
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What does the bottom number of a column vector show?
The vertical move, up if positive.
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What does \(\overrightarrow{AB}\) mean?
The vector from \(A\) to \(B\).
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What is \(\overrightarrow{BA}\) in terms of \(\overrightarrow{AB}\)?
\(-\overrightarrow{AB}\).
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How do you find a vector from two coordinates?
Subtract the coordinates of the start from the end.
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How do you add column vectors?
Add the top numbers and add the bottom numbers.
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How do you subtract column vectors?
Subtract the top numbers and subtract the bottom numbers.
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How do you multiply a vector by a number?
Multiply both numbers in the column by it.
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When are two vectors equal?
When they have the same size and direction.
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When are two vectors parallel?
When one is a multiple of the other.
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What does a negative multiple of a vector do?
It points in the opposite direction.
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How do you draw \(\mathbf{a} + \mathbf{b}\)?
Draw \(\mathbf{b}\) starting from the end of \(\mathbf{a}\), then join the start to the finish.
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How do you draw \(\mathbf{a} - \mathbf{b}\)?
Add \(\mathbf{a}\) and \(-\mathbf{b}\).
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How do you find the length of a column vector?
Use Pythagoras' theorem on the two numbers (Higher tier).
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What is the length of \(\begin{pmatrix} 3 \\ 4 \end{pmatrix}\)?
5 (Higher tier).