How do you compute the dot product to find the magnitude of $u=20i+25j$ ?

Question

5043 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-10-01T16:37:18

You do not use the dot-product, to compute the magnitude; you use $|u| = sqrt(20^2 + 25^2)$

$|u| = sqrt1025$

$|u| = sqrt(20^2 + 25^2)$

$|u| = sqrt(400 + 625)$

$|u| = sqrt1025$

How do you compute the dot product to find the magnitude of u=20i+25ju=20i+25j?