Respuesta :

a · b = 7·3 +4·5 = 21 +20 = 41
Answer  = 41


Explanation

a · b is a scalar product.

a = <x₁, y₁> = <7, 4>
x₁ = 7
y₁ = 4

b = <x₂, y₂> = <3, 5>
x₂ = 3
y₂ = 5

a · b = (x₁ * x₂) + (y₁ * y₂)
= (7 * 3) + (4 * 5)
= 21 + 20
= 41

a · b = 41