Question

Dada a função f (x)=1- 5/2x calcule:

a) f(0)
b) f (-1)
c) f (2)
d) f (-2)
e) f (5)
f) f (1/5)

Answer 1

A)

f(0) = $1- \frac{5}{2} .0$
f(0) = $1-0$
f(0) = $1$

B)

f(-1) = $1 - \frac{5}{2}.-1$
f(-1) = $1 + \frac{5}{2}$
f(-1) = $\frac{7}{2}$

C)

f(2) = $1 - \frac{5}{2}.2$
f(2) = $1 - \frac{10}{2}$
f(2) = $1 - 5$
f(2) = $- 4$

D)

f(-2) = $1 - \frac{5}{2}.-2$
f(-2) = $1 + \frac{10}{2}$
f(-2) = $1 + 5$
f(-2) = $6$

E) 

f(5) = $1 - \frac{5}{2}.5$
f(5) = $1 - \frac{25}{2}$ → Fazendo o MMC (2)
f(5) = $\frac{2}{2} - \frac{25}{2}$
f(5) = $\frac{23}{2}.x$

F)

f($\frac{1}{5}$) = $1 - \frac{5}{10}$
f($\frac{1}{5}$) = $1 - \frac{1}{2}$
f($\frac{1}{5}$) = $0,5$