Why does a historian have to understand what a point of view is?

A point of view is important because it shows who is telling the story of what happened and thus clues them in to whether the story teller may be biased, not know everything that happened, or simply perceive what happened in a different way than what may have happened.

answer

explanation

the given equation is

we can rewrite this as:

let

then the equation becomes:

the factors of 8 that sum up to -9 are {-1,-8}

we split the middle term with these factors to obtain,

we factor by grouping to obtain:

apply the zero product property to get:

but

offline recommendation systems option b

because recommendation systems produce a list of two ways

1. through collaborative filtering

or

2. through content-based filtering