(x+4)^2-9*(x-4)^2
(x^2+8x+16)-9*(x^2-8x+16)
x^2+8x+16-9x^2+72x-144
-8x^2+80x-128
F(x) = 3x^2 - 1
f'(x) = (3x^2 - 1)' = 6x
f'(2)= 6*2= 12
40m + 3n = 13
20m - 7n = - 5
Решение
- 40m + 14n = 10
17n = 23
n = 23/17 = 1 6/17
20m - 7•( 23/17 ) = - 5
20m = - 5 + ( 161/17 )
20m = - 5 + 9 8/17
20m = 4 8/17
m = 76/17 : 20
m = 38/170
F(x)=(3x+1)²-3=9x²+6x+1-3=9x²+6x-2
f(x)'=18x+6
f(2/3)=18*2/3+6=12+6=18
3a+5-12a+6+4a= -5a+11. подставляем значение: (-5)*(-12)+11=60+11=71. Ответ: 71.