Question

Dados as funções f ( x ) = - 4x - 10 e g ( x ) = 2 + 4x. Calcule
A ) f ( -3 )
B ) g ( -4 )
C ) f ( -4 ) + g ( -2 ) + f ( -1 )
D ) g ( -3 ) - g ( -5 ) + f ( -4 )
E ) g ( -6 ) - f ( -2 ) + f ( 5 )

Answer 1

Basta substituir 

A ) f ( -3 )
  f ( x ) = - 4x - 10
f(-3) = -4*(-3) -10
f(-3) = 12 -10
f(-3) = 2

B ) g ( -4 ) 
  g ( x ) = 2 + 4x
g(-4) = 2 + 4*(-4)
g(-4) =  2+ (-16)
g(-4) = -14

C ) f ( -4 ) + g ( -2 ) + f ( -1 ) 
  f ( -4 ) = - 4 *(-4)  - 10 
f(-4) = 16 -10
f(-4) = 6

  g ( -2 ) = 2 + 4 *(-2)
g(-2) = 2 + (-8)
g(-2) = -6

  f ( -1 ) = - 4 *(-1) - 10
f(-1) = 1 - 10
f(-1) = -9

6 + (-6) + (-9) = -9

D ) g ( -3 ) - g ( -5 ) + f ( -4 )
  g ( -3 ) = 2 + 4x
g(-3) = 2 + 4* (-3)
g(-3) = 2 + (-12)
g(-3) = -10

  g ( -5 ) = 2 + 4x
g(-5) = 2 + 4 *(-5)
g(-5) = 2+ (-20)
g(-5) = -18

  f ( x ) = - 4x - 10
f(-4) = -4 * (-4) - 10
f(-4) = 16 -10
f(-4) = 6

(-10) - (-18) + 6 = 14
 
E ) g ( -6 ) - f ( -2 ) + f ( 5 )
  g ( -6 ) = 2 + 4x
g(-6) = 2 + 4 * (-6)
g(-6) = 2 + (-24)
g(-6) = -22

  f ( -2 ) = - 4x - 10
f(-2) = -4 * (-2) -10
f(-2) = 8 - 10
f(-2) = -2 

  f ( 5 ) = - 4x - 10
f(5) = -4 *(5) -10
f(5) = -20 - 10
f(5) = -30

(-22) - (-2) + (-30) = -50