Question

sejua função f : IR -> IR definida por f(x)=-2x²-x. calcule:
 a) f(-2)
 b) f(3)
 c)f(1)=
 d)f(1/2)

Answer 1

$f(x)=-2x^2-x\\ a) \ f(-2)=-(-2)^2-(-2)=-4+2=-2\\ b) \ f(3)=-3^2-3=-9-3=-12\\ c) \ f(1)=-1^2-1=-1-1=-2\\ d) \ f(\frac{1}{2})=-(\frac{1}{2})^2-\frac{1}{2}=-\frac{1}{4}-\frac{1}{2}=-\frac{3}{4}$