Find the domain of the function f ( x ) = 2 x 2 − 1 x + 4 Use interval notation to express your answer.

Question

Find the domain of the function 

Use interval notation to express your answer.

Answer 1

f(x) = 2x^2 -x + 4

is an upward opening parabola where x can be any real number

the domain is any real number. In interval notation (-infinity, +infinity)

instead of "infinity" use an "8" on its side. most keyboards don't seem to have it.

f(x) = 2(x -x/2 + 1/16) + 4- 1/8

f(x) = 2(x-1/4)^2 + 31/8 where (1/4, 31/8) is the vertex and minimum point

the range is y>31/8 or in interval notation (31/8, +infinity) 31/8 = 3 7/8

y is = 3 7/8 or > 3 7/8,

but domain is any real number