Question

1)(2.00) Podemos afirmar que o zero da função f(x) = -2x + 5 é igual a: (a) 2 (b) 2,5 (C) -2,5 (d) 3​

Answer 1

Resposta:

$f\left(x\right)\:=\:-2x\:+\:5\\\\\mathrm{Dominio\:de\:}\:-2x+5\::\quad \begin{bmatrix}\mathrm{Solucao:}\:&\:-\infty \:<x<\infty \\ \:\mathrm{Notacao\:intervalo}&\:\left(-\infty \:,\:\infty \:\right)\end{bmatrix}\\\\\mathrm{Imagem\:de\:}-2x+5:\quad \begin{bmatrix}\mathrm{Solucao:}\:&\:-\infty \:<f\left(x\right)<\infty \\ \:\mathrm{Notacao\:intervalo}&\:\left(-\infty \:,\:\infty \:\right)\end{bmatrix}\\\\\mathrm{Paridade\:de}\:-2x+5:\quad \mathrm{Nao\:e\:par\:nem\:impar}$

$\mathrm{Pontos\:de\:interseccao\:com\:o\:eixo\:de}\:-2x+5:\quad \mathrm{X\:intersepta}:\:\left(\frac{5}{2},\:0\right),\:\mathrm{Y\:intersepta}\\\\\mathrm{Inversa\:de}\:-2x+5:\quad -\frac{x-5}{2}\\\\\mathrm{Inclinacao\:de\:}-2x+5:\quad m=-2\\\\-2x+5\\\\\mathrm{Para\:a\:equacao\:de\:reta\:da\:forma\:}\mathbf{y=mx+b}\mathrm{,\:a\:inclinacao\:e\:}\mathbf{m}\\\\m=-2<<a)<<2>>a))<<<<$

Answer 2

Resposta:

c) -2,5

Explicação passo-a-passo:

$1) \: f(x) = - 2x + 5 \\ - 2x + 5 = 0 \\ - 2x = 5 \\ x = - \frac{5}{2}$

$x = - 2.5$