Question

1.1 Найдите значение функции y=f(x) в заданных точках:
a) f(x) = 2x² + 3, x = -1; 2,5; 3;
б) f(x) = 1/3 - 5x, x = -0,5; 1/15; 0;
в) f(x) = 5/x - 3 + 2, x = 4; 5; 1/2;
г) f(x) = 2/2+x, x = -1; 0; -1/5. ​

Answer 1

Ответ:

a) f(-1) = 2*(-1)² + 3 = 2 + 3 = 5

f(2,5) = 2*(2,5)² + 3 = 2*6,25 + 3 = 12,5 + 3 = 15,5

f(3) = 2*(3)² + 3 = 2*9 + 3 = 18 + 3 = 21

б) f(-0,5) = 1/3 - 5*(-0,5) = 1/3 + 2,5 = 2,833

f(1/15) = 1/3 - 5*(1/15) = 1/3 - 1/3 = 0

f(0) = 1/3 - 5*0 = 1/3

в) f(4) = 5/4 - 3 + 2 = 1,25 - 3 + 2 = 0,25

f(5) = 5/5 - 3 + 2 = 1 - 3 + 2 = 0

f(1/2) = 5/(1/2) - 3 + 2 = 10 - 3 + 2 = 9

г) f(-1) = 2/(2+(-1)) = 2/1 = 2

f(0) = 2/(2+0) = 2/2 = 1

f(-1/5) = 2/(2+(-1/5)) = 2/(2-1/5) = 2/(10/5-1/5) = 2/(9/5) = 10/9