Question

Estude a variação do sinal das seguintes funções afins:
a) y = x + 4

b) y = -2x + 1

c) y = 3x + 5

Answer 1

Resposta:

$y = x + 4\\\\\left(x+4\right)\\\\=\frac{d}{dx}\left(x\right)+\frac{d}{dx}\left(4\right)\\\\=1+0\\\\=1$

$y = -2x + 1\\\\\left(-2x+1\right)\\\\=-\frac{d}{dx}\left(2x\right)+\frac{d}{dx}\left(1\right)\\\\=-2+0\\\\=-2$

$y = 3x + 5\\\\\left(3x+5\right)\\\\=\frac{d}{dx}\left(3x\right)+\frac{d}{dx}\left(5\right)\\\\=3+0\\\\=3$