Question

Find the angle between the vectors (9,-1 ) and (4,2). Carry your intermediate computations to at

least 4 decimal places, Round your final answer to the nearest degree.

Answer 1

33°

Explanation:

(9 , -1), (4 , 2)

cos α = (x₁ * x₂ + y₁ * y₂) / (√(x₁² + y₁²) * √(x₂² + y₂²))

x₁ = 9,

x₂ = 4,

y₁ = -1,

y₂ = 2

cos α = (9*4 + -1*2) / (√(81+1) * √(16+4))

= 34/ (√82 * √20)

≈ 0.8396

α = 32.91° ≈ 33°