How do you find the domain and range of g(x)=-x^2-3x-1g(x)=x23x1?

1 Answer
Mar 31, 2017

Domain: x in RR . Range: g(x)<=1.25

Explanation:

g(x)= -x^2-3x-1 , a= -1, b= -3 , c= -1
Domain (possible value of x): Any real value i.e x in RR

Range: This is an equation of parabola , opening downwards, since a is negative.
Vertex(x) = -b/(2a)= 3/ -2=-1.5
Vertex(y) g(x)= -(-1.5)^2 -3*(-1.5) -1 = 1.25

Vertex is at ( -1.5 , 1.25) :. 1.25 is the maximum point.
Therefore Range, g(x)<=1.25 graph{-x^2-3x-1 [-10, 10, -5, 5]} [Ans]