Show that the angle between `vecA=hati-5hatj and vecB = 2hati - 10hatj` is zero.

Explanation

We are given: `vecA=hati-5hatj,vecB=2hati-10hatj`
We are to calculate, Angle between `vecA and vecB` is `0^@` .
We know that, the angle between the vectors is zero if `vecAxx vecB=0`
`vecAxxvecB=|(hati,hatj,hatk),(1,-5,0),(2,-10,0)|=hati(0-0)+hatj(0-0)+hatk(-10+10)=0`
So angle between `vecA and vecB ` is `0^@`