For this case we have the following vectors:
[tex]a = 4i - 4j\\b = 4i + 5j[/tex]
We must find the product point of both vectors.
To do this, we multiply component by component and add the results.
We have then:
[tex]a.b = (4) (4) + (-4) (5)\\a.b = 16 -20\\a.b = -4[/tex]
Answer:
The point product of both vectors is given by:
[tex]a.b = -4[/tex]
