Question

dada a funcao f(x)=2x-4x+2, calcule f(1)-f(3)

Answer 1

[ f(x) = 2x - 4x + 2 ] 
 
f(1) = 2.1 - 4.1 + 2 = 2 - 4 + 2 = -2 + 2 = 0
f(3) = 2.3 - 4.3 + 3 = 6 - 12 + 3 = -6 + 3 = -3

f(1) - f(3) = 0 - (-3) = 0 + 3 = 3

Espero ter ajudado! :))

Answer 2

f(1) = 2x1 - 4x1 + 2 = 2 - 4 + 2 = 0
f(3) = 2x3 - 4x3 + 2 = 6 - 12 + 2 = - 4
 f(1) - f(3) = 0 - (-4) = + 4