MAT2611 ASSIGNMENT 1 2023
Problem 3
𝑉 = ℝ2
𝒖 = (𝑢1 , 𝑢2 ), 𝒗 = (𝑣1 , 𝑣2 ) ∈ 𝑉
𝒖 + 𝒗 = (𝑢1 + 𝑣1 − 1, 𝑢2 + 𝑣2 − 1)
𝑘𝒖 = (𝑘𝑢1 , 𝑘𝑢2 ) 𝑘∈ℝ
(a)
𝒖 = (1, −2), 𝒗 = (3, 0), 𝑘=4
𝒖 + 𝒗 = (1 + 3 − 1, −2 + 0 − 1)
𝒖 + 𝒗 = (4 − 1, −2 − 1)
𝒖 + 𝒗 = (3, −3)
𝑘𝒖 + (−𝒗) = 4(1, −2) + (−1)(3, 0)
𝑘𝒖 + (−𝒗) = (4 × 1, 4 × −2) + (−1 × 3, −1 × 0)
𝑘𝒖 + (−𝒗) = (4, −8) + (−3, 0)
𝑘𝒖 + (−𝒗) = (4 + (−3) − 1, −8 + 0 − 1)
𝑘𝒖 + (−𝒗) = (1 − 1, −8 − 1)
𝑘𝒖 + (−𝒗) = (0, −9)
(b)
Let 𝒖 = (𝑢1 , 𝑢2 )
𝒖 + (0, 0) = (𝑢1 , 𝑢2 ) + (0, 0)
𝒖 + (0, 0) = (𝑢1 + 0 − 1, 𝑢2 + 0 − 1)
𝒖 + (0, 0) = (𝑢1 − 1, 𝑢2 − 1)
𝒖 + (0, 0) ≠ (𝑢1 , 𝑢2 )
𝒖 + (0, 0) ≠ 𝒖
Similarly, (0, 0) + 𝒖 ≠ 𝒖
Problem 3
𝑉 = ℝ2
𝒖 = (𝑢1 , 𝑢2 ), 𝒗 = (𝑣1 , 𝑣2 ) ∈ 𝑉
𝒖 + 𝒗 = (𝑢1 + 𝑣1 − 1, 𝑢2 + 𝑣2 − 1)
𝑘𝒖 = (𝑘𝑢1 , 𝑘𝑢2 ) 𝑘∈ℝ
(a)
𝒖 = (1, −2), 𝒗 = (3, 0), 𝑘=4
𝒖 + 𝒗 = (1 + 3 − 1, −2 + 0 − 1)
𝒖 + 𝒗 = (4 − 1, −2 − 1)
𝒖 + 𝒗 = (3, −3)
𝑘𝒖 + (−𝒗) = 4(1, −2) + (−1)(3, 0)
𝑘𝒖 + (−𝒗) = (4 × 1, 4 × −2) + (−1 × 3, −1 × 0)
𝑘𝒖 + (−𝒗) = (4, −8) + (−3, 0)
𝑘𝒖 + (−𝒗) = (4 + (−3) − 1, −8 + 0 − 1)
𝑘𝒖 + (−𝒗) = (1 − 1, −8 − 1)
𝑘𝒖 + (−𝒗) = (0, −9)
(b)
Let 𝒖 = (𝑢1 , 𝑢2 )
𝒖 + (0, 0) = (𝑢1 , 𝑢2 ) + (0, 0)
𝒖 + (0, 0) = (𝑢1 + 0 − 1, 𝑢2 + 0 − 1)
𝒖 + (0, 0) = (𝑢1 − 1, 𝑢2 − 1)
𝒖 + (0, 0) ≠ (𝑢1 , 𝑢2 )
𝒖 + (0, 0) ≠ 𝒖
Similarly, (0, 0) + 𝒖 ≠ 𝒖