What is the projection of (8i + 12j + 14k)(8i+12j+14k) onto (3i – 4j + 4k)?

1 Answer
Jul 29, 2018

The projection is =(32)/41*<3,-4,4>

Explanation:

The vector projection of vecb onto veca is

proj_(veca)vecb=(veca.vecb)/(|veca|^2)veca

Here,

veca= <3,-4,4>

vecb = <8,12,14>

Therefore,

The dot product is

veca.vecb=<3,-4,4> . <8,12,14> =24-48+56=32

The modulus of veca is

|veca| = |<3,-4,4>| = sqrt(9+16+16)= sqrt41

Therefore

proj_(veca)vecb=(32)/41*<3,-4,4>