Question

construa o gráfico da função f(x)=3x+x-3 para os seguintes valores de x -7 a 7​

Answer 1

$\Large\boxed{\begin{array}{l}\sf f(x)=3x+x-3\\\sf somando\,3x\,com\,x\,teremos:\\\sf f(x)=4x-3\\\sf se\,x=-7\\\sf f(-7)=4\cdot(-7)-3=-28-3=-31\\\sf se\,x=-6\\\sf f(-6)=4\cdot(-6)-3=-24-3=-27\\\sf se\,x=-5\\\sf f(-5)=4\cdot(-5)-3=-20-3=-23\\\sf se\,x=-4\\\sf f(-4)=4\cdot(-4)-3=-16-3=-19\\\sf se\,x=-3\\\sf f(-3)=4\cdot(-3)-3=-12-3=-15\\\sf se\,x=-2\\\sf f(-2)=4\cdot(-2)-3=-8-3=-11\\\sf se\, x=-1\\\sf f(-1)=4\cdot(-1)-3=-4-3=-7\\\sf se\,x=0\\\sf f(0)=4\cdot0-3=0-3=-3\\\sf se\,x=1\\\sf f(1)=4\cdot1-3=4-3=1\\\sf x=2\\\sf f(2)=4\cdot2-3=8-3=5\\\sf se\,x=3\\\sf f(3)=4\cdot3-3=12-3=9\\\sf se\,x=4\\\sf f(4)=4\cdot4-3=16-3=13\\\sf se\,x=5\\\sf f(5)=4\cdot5-3=20-3=17\end{array}}$

$\Large\boxed{\begin{array}{l}\sf se\,x=6\\\sf f(6)=4\cdot6-3=24-3=21\\\sf se\,x=7\\\sf f(7)=4\cdot7-3=28-3=25\end{array}}$

$\Large\boxed{\begin{array}{l}\sf f(x)=3x+x-3\implies f(x)=4x-3\\\boxed{\begin{array}{c|c}\sf x&\sf f(x)\\\sf-7&\sf-31\\\sf-6&\sf-27\\\sf -5&\sf-23\\\sf -4&\sf-19\\\sf -3&\sf-15\\\sf -2&\sf-11\\\sf -1&\sf-7\\\sf 0&\sf-3\\\sf1&\sf1\\\sf2&\sf5\\\sf3&\sf9\\\sf4&\sf13\\\sf5&\sf17\\\sf6&\sf21\\\sf7&\sf25\end{array}}\end{array}}$