Answer:
a ⋅ b = 67
Step-by-step explanation:
We have been given that
a = 10i+9j
b = 4i +3j
The dot product of a ⋅ b is given as
[tex]a\cdot b=(10i+9j)( 4i +3j)\\\\=10i\cdot4i+30ij+9i\cdot3j+36ij[/tex]
Now, we know that
i⋅ i = 1
j ⋅ j=1
i⋅ j=0
Hence, we have
[tex]10i\cdot4i+9i\cdot3j=40+27\\\\=67[/tex]
Therefore, we have
a ⋅ b = 67
