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2 years ago

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

Mathematics

1 answer:

nasty-shy [4]2 years ago

7 0

Answer:

33°

Step-by-step 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°

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