Science

Math

Humanities

... and beyond

Socratic Meta
Featured Answers

Topics

How do you find the projection of u=<4,8> onto v=<-1,2>?

1 Answer

Vinícius Ferraz

May 28, 2017

#(-12/5, 24/5)#

Explanation:

#u * v = ||u|| * ||v|| * cos theta#

But you want #||u|| * cos theta * hat v = frac{u * v}{||v||} * frac{v}{||v||} = frac{u*v}{v*v}*v#

#= frac{4(-1) + 8*2}{(-1)^2 + 2^2} * (-1, 2)#

#= frac{12}{5} * (-1, 2)#

Related questions

See all questions in Vector Projection

Impact of this question

2245 views around the world

You can reuse this answer
Creative Commons License