Question

Dados f(2)=-3 e f(-1)=3.Determine a função afim.

Answer 1

$Dada\ a f(x)=ax+b\ calcular\ f(x):\\ \left \{ {{f(2)=-3} \atop {f(-1)=3}} \right.\\\\ \left \{ {{2a+b=-3} \atop {-a+b=3}} \right.\ Subtraindo\ as\ equac\~oes:\\3a=-6\\a=-2\\\\2a+b=-3\\2(-2)+b=-3\\b=-3+4\\b=1\ Logo\ f(x)=-2x+1$