Question

1- Construir o gráfico das funções de R em R.
a)Y=2x -1
b) Y = 3x+2

Answer 1

$y=2x-1 \\ \\ se~~y=0 \\ 2x-1=0 \\ 2x=-1 \\ x=- \frac{1}{2} \\ \\ ponto~~(- \frac{1}{2},0)~~corta~~eixi~~x \\ \\ se~~x=0 \\ y=2(0)-1 \\ y=-1 \\ \\ ponto~~(0,-1)~~corta~~eixo~~y$
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$b) \\ y=3x+2 \\ \\ se~~y=0 \\ 3x+2=0 \\ 3x=-2 \\ x=- \frac{2}{3} \\ \\ ponto~~(- \frac{2}{3} ,0)~~corta~~eixo~~x \\ \\ se~~x=0 \\ y=3(0)+2 \\ y=2 \\ \\ ponto~~(0,2)~~corta~~eixo~~y$