Question

380. Найдите значение выражения: 1) 9a^3 -a (3a + 2)^2 + 4a (3a + 7), при a = -1 1/6; 2 ) (2y - 5) ^2- 4(y - 3)^2- 4y, npu y= - 2/7; 3) 25m (m — 1) - (5m – 3)^2 - 6m, при m = -0,3; 4) 24x^2 -(7x-2)^2 +(5x - 3)(5x + 1), при x =- 5/9 . Пожалуйста помогите срочна нужна​

Answer 1

Здравствуй azizaallayarova800!

Найдите значение выражения:

Для начала, мы будем упрощать выражения и затем приступать к подстановке чисел. А также можно сразу подставить числа и так решить, но для меня этот способ не удобен. Приступлю к решению:

1) 9a³ -a(3a + 2)² + 4a(3a + 7)= 9a³ - a(9a²+12a+4) + 12a² + 28a = 9a³ - 9a³ - 12a² - 4a + 12a² + 28a = 24a

при a = $-1\frac{1}{6}$, то  $24*(-1\frac{1}{6}) = 24* (-\frac{7}{6}) = -28$

(и тут я не до конца понял, поэтому решу и так)

при $a=-\frac{11}{6}$, то $24*(-\frac{11}{6})= 4*(-11) = -44$

Ответ:  -28 или -44

2 ) (2y - 5)²- 4(y - 3)²- 4y= 4y² - 20y + 25 - 4(y² - 6y + 9) - 4y = 4y² - 20y + 25 - 4y² + 24y - 36 - 4y = - 11

Значит, в данном выражения подстановка чисел не нужна

Ответ: -11

3) 25m (m — 1) - (5m – 3)² - 6m=25m² - 25m - (25m² - 30m + 9) - 6m = 25m² - 25m - 25m² + 30m - 9 - 6m = - m - 9

при m = -0.3, то:  - (- 0,3) - 9 = 0,3 - 9 = - 8,7

Ответ: -8,7

4) 24x² -(7x-2)² +(5x - 3)(5x + 1)= 24x² - (49x² - 28x + 4) + 25x² + 5x - 15x - 3= 24x² - 49x² + 28x - 4 + 25x² - 10x - 3 = 49x² - 49x² + 18x - 7 = 18x - 7

при x = - 5/9, то:  $18 * (-\frac{5}{9}) -7= -10-7=-17$

Ответ: -17

Удачи в дальнейших решениях!

Answer 2

1) При a = -1 1/6: 9(-1 1/6)^3 - (-1 1/6) + (3(-1 1/6) + 2)^2 + 4(-1 1/6) + (3(-1 1/6) + 7) = 9(-223/216) + 7/6 + (3(-223/216) + 2)^2 + 4(-223/216) + (3(-223/216) + 7) = -1677/216 + 7/6 + (2/216)^2 + 4(-223/216) + (7/216) = -1677/216 + 84/216 + 4/216 + 4(-223/216) + 7/216 = -1593/216 - 892/216 + 7/216 = -2478/216 = -41/3

2) При y = -2/7: (2(-2/7) - 5)^2 - 4(-2/7 - 3)^2 - 4(-2/7) = ( -4/7 - 5)^2 - 4(-23/7)^2 + 8/7 = (-39/7)^2 - 4(529/49) + 8/7 = 1521/49 - 2116/49 + 8/7 = -595/49 + 392/49 = -203/49

3) При m = -0,3: 25(-0,3)(-0,3 - 1) - (5(-0,3) - 3)^2 - 6(-0,3) = 25(0,3)(-1,3) - ( -1,5 - 3)^2 + 1,8 = 25(-0,39) - (-4,5)^2 + 1,8 = -9,75 - 20,25 + 1,8 = -28,2

4) При x = -5/9: 24(-5/9)^2 - (7(-5/9) - 2)^2 + (5(-5/9) + 3)(5(-5/9) + 1) = 24(25/81) - ( -35/9 - 2)^2 + ( -25/9 + 3)( -25/9 + 1) = 600/81 - ( -37/9)^2 + ( -25/9 + 3)( -25/9 + 1) = 200/27 - 1369/81 + ( -25/9 + 3)( -25/9 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100/81 + 3)( -100/81 + 1) = 200/27 - 1369/81 + ( -100