Question

ДАЮ 50 БАЛЛОВ!! Найдите тождество. 13.17 только 2

Answer 1

(c+2)²-(c-4)(3-c)-0,5(4c²-1)=16,5-3c;

c²+4c+4+c²-7c+12-2c²-0,5=16,5-3c;

16,5-3c=16,5-3c;

Answer 2

$2) \: \: {(c + 2)}^{2} - (c - 4)(3 - c) - 0.5(4 {c}^{2} - 1) = \\ = {c}^{2} + 4c + 4 - (3c - {c}^{2} - 12 + 4c) - 2 {c}^{2} + 0.5 = \\ = {c}^{2} + 4c + 4 + {c}^{2} - 7c + 12 - 2 {c}^{2} + 0.5 = \\ = 16.5 - 3c$

Тождество доказано.