Question

The function f(x) is to be graphed on a coordinate plane.

f(x) = StartLayout Enlarged left-brace 1st row 1st column negative x, 2nd column x less-than 0 2nd row 1st column 1, 2nd column x greater-than-or-equal-to 0 EndLayout

At what point should an open circle be drawn?

(–1, 0)
(0, 0)
(0, 1)
(1, 0)

Answer 1

(0, 0)

Reason: For x < 0, f(x) = -x, which approaches 0 as x → 0⁻, but x = 0 is not included in that piece, so the point (0, 0) is an open circle. The value at x = 0 is f(0) = 1 (closed dot at (0,1)).