Question

AJUDEMMM! 1_Dadas as funções f(x) = 2x + 5 e g(x) = x2 – 2,
determinar:

a) (gf)(3) b) (fg)(x)

2- Seja f uma função real de variável real tal que f(3x -2) = 6x + 1.
Determinar:

a) f(4) b) f(x)

Obg!​

Answer 1

Resposta:

1)

f(×) = 2× + 5 g(×) = ×2 - 2

f(1) = 2 . 1 + 5 g(1) = 1 . 2 - 2

f(1) = 2 + 5 g(1) = 2 - 2

f(1) = 7 g(1) = 0

f(2) = 2 . 2 + 5 g(2) = 2 . 2 - 2

f(2) = 4 + 5 g(2) = 4 - 2

f(2) = 9 g(2) = 2

f(3) = 2 . 3 + 5 g(3) = 3 . 2 - 2

f(3) = 6 + 5 g(3) = 6 - 2

f(3) = 11 g(3) = 4

f(×)=2 // g(×)=2

a- (gf)(3)

(gf)(3) = ?

2 . 2 . 3 = 12

_______________

b- (fg)(x)

2 . 2 . 2 = 8

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2)

f(3× - 2) = 6× + 1

a- f(4)

f(4) (3 . 4 - 2) = 6 . 4 + 1

f(4) (12 - 2) = 24 + 1

f(4) 10 = 25

f(4) 25 - 10 = 15

_______________

b- f(×)

f(0) =

(3 . 0 - 2) = 6 . 0 + 1

-2 = +1

= +1 +2

f(0)= 3

f(1) =

(3 . 1 - 2) = 6 . 1 + 1

3 - 2 = 6 + 1

1 = 7

= 7 - 1

f(1)= 6

f(2)=

(3 . 2 - 2) = 6 . 2 + 1

6 - 2 = 12 + 1

4 = 13

= 13 - 4

f(2)= 9

f(×) = 3

Acredito que seja isso

espero ter ajudado