Question

СРОЧНО ПОМОГИТЕ❗❗❗❗​

Answer 1

$1.1)(3a - 2b)(3a + 2b) = 9 {a}^{2} - 4 {b}^{2} \\ 2)(a + 3) {}^{2} = {a}^{2} + 2 \times 3 \times a + {3}^{2} = {a}^{2} + 6 a + 9 \\ 3)(2a - 3) {}^{2} = 4 {a}^{2} - 2 \times 2a \times 3 + {9}^{2} = 4 {a}^{2} - 12a + 81 \\ 4)(a + 3) {}^{3} = {a}^{3} + 3 {a}^{2} \times 3 - 3a \times {3}^{2} + {3}^{3} = {a}^{3} + 9 {a}^{2} - 27a + 27$

$2.1)9 {x}^{2} - 25 {y}^{2} = (3x - 5y)(3x + 5y) \\ 2)4 {x}^{2} - (x + 1) {}^{2} = (2x - x + 1)(2x + x + 1) = (x + 1)(3x + 1) \\ 3) {x}^{2} + 14x + 49 = (x + 7) {}^{2}$

$3.1)198 {}^{2} - {202}^{2} = (198 - 202)(198 + 202) = - 2 \times 400 = - 800 \\ 2) {518}^{2} - {482}^{2} = (518 - 482)(518 + 482) = 36 \times 1000 = 36000$