Question
Find the magnitude of the vector $ \| \vec{v} \| = \left(2,~-4\right) $ .
Answer
The magnitude of vector $ \vec{v} $ is $ \| \vec{v} \| = 2 \sqrt{ 5 } $ .
Explanation
To find magnitude of a vector $ v=(a,b) $ we use formula $ ||v|| = \sqrt{a^2+b^2} $
In this example $ a = 2 $ and $ b = -4 $, so:
$$ ||v|| = \sqrt{ 2^2 + (-4)^2 } = \sqrt{ 4 + 16 } = \sqrt{ 20 } = 2 \sqrt{ 5 }$$This page was created using
Vectors Calculator