Question

помоги доброму парню решить ​

Answer 1

Ответ:

Пошаговое объяснение:

$c=a - 2b = (a_x - 2b_x; a_y - 2b_y) = {(-3) - 2*2; 2 - 2*(-1)} = {-3 - 4; 2 - (-2)} =\\=(-7; 4)$

|c| = $\sqrt{a_x^2 + a_y^2 }= \sqrt{(-7)^2 + 4^2} = \sqrt{49 + 16} = \sqrt{ 65}$

$c=-3a - 2b = ((-3)a_x - 2b_x; (-3)a_y - 2b_y) =\\= ((-3)*(-3) - 2*2; (-3)*2 - 2*(-1)) = (9 - 4; -6 - (-2)}) = (5; -4)$

|c|= $\sqrt{a_x^2 + a_y^2 }= \sqrt{5^2 + (-4)^2} = \sqrt{25 + 16} = \sqrt{ 41}$

$c=2a + b = (2a_x + b_x; 2a_y + b_y) = (2*(-3) + 2; 2*2 + (-1)) = \\=(-6 + 2; 4 + (-1)) = (-4; 3)$

|c|= $\sqrt{a_x^2 + a_y^2 }= \sqrt{(-4)^2 + 3^2} = \sqrt{16 + 9} = \sqrt{ 25}=5$

$c=a - b = (a_x - b_x; a_y - b_y) = ((-3) - 2; 2 - (-1)) = (-5; 3)$

|c|= $\sqrt{a_x^2 + a_y^2 }= \sqrt{(-5)^2 + 3^2} = \sqrt{25 + 9} = \sqrt{ 34}$