Question

Решите задания 46 и 47.

Answer 1

$46. \ f(x) = \frac{1}{6} x^2- \frac{1}{4}x+15 \\ f'(x) = \frac{x}{3} - \frac{1}{4} \\ \frac{x}{3} = \frac{1}{4} \\ 4x= 3 \\ x = \frac{3}{4} = 0,75 \\ \\ 47. \ f(x) = \frac{1}{4} x^2- \frac{1}{5}x +12 \\ f'(x) = \frac{x}{2} - \frac{1}{5} \\ \frac{x}{2} = \frac{1}{5} \\ 5x=2 \\ x = \frac{2}{5} = 0,4$

Answer 2

46
f`(x)=1/3*x-1/4=0
1/3x=1/4
x=1/4:1/3=3/4=0,75
ответ Е
47
f`(x)=1/28x-1/5=0
1/2*x=1/5
x=1/5:1/2=2/5=0,4
Ответ Е