For each of the following determine the domain Express your

. For each of the following, determine the domain. Express your answers in interval notation.

(a) f(x) = x 2 + 3x + 2

(b) f(x) = x 3

(c) f(x) = 1 x 4

Solution

a) f(x) = x^2 +3x +2

Its a polynomail function with no restrictions on x values it can take.

So, Domain: ( -inf , +inf)

b) f(x) = sqrt(x-3)

For real function the value inside the sqrt must be > = to zero.

Domain : x-3> =0----> x>=3 -----> [ 3, +infinity )

c) f(x) = 1x -4

Domain : All real values of x ( -infinity , +infinity)