Question

1) Dada a função F definida por F(x)=5x-8, calcule:

A)f (-2)
B)f (raiz 2)
C)x tal que F(x)=0
D)X tal que F(x)=19

Answer 1

Olá!! fabrina30 !!

Resolução!!!

f ( x ) = 5x - 8

a)

f ( x ) = 5x - 8
f ( - 2 ) = 5 • ( - 2 ) - 8
f ( - 2 ) = - 10 - 8
f ( - 2 ) = - 18

b)

f ( x ) = 5x - 8
f ( √2 ) = 5 • ( √2 ) - 8
f ( √2 ) = 5√2 - 8

c)

f ( x ) = 5x - 8
0 = 5x - 8
5x - 8 = 0
5x = 8
x = 8/5

d)

f ( x ) = 5x - 8
19 = 5x - 8
5x - 8 = 19
5x = 19 + 8
5x = 27
x = 27/5

Espero ter ajudado!!!