Question

determine suas raízes e classifique a função em descente e decrescente

a) f (x) =2x
b)f (X) =_3x-6
c)y=_5x+15

Answer 1

a) f (x) = 2x                         crescente

2x = 0 ==> x = 0 ==> x = 0
                        2
====================================================
b)f (X) = - 3x-6        decrescente

-3x - 6 = 0 ==> -3x = 6(-1) ==> 3x = - 6 ==> x = - 2
=======================================================       c)y= - 5x+15  decrescente

-5x + 15 = 0 ==> -5x = -15(-1) ==> 5x = 15 ==> x = 3