The ornamental design for a notebookcomputer, as shown and described.
FIG. 1 is a perspective view of a notebook computer, showing our new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left-side view thereof;
FIG. 5 is a right-side view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is an enlarged view of the portion X encircled in FIG. 5.
The broken lines illustrate environmental structure and form no part of the claimed design. The dot-dot-dash lines encircle portions of the claimed design that are illustrated in enlargements and form no part of the claimed design. The shade lines in the figures show contour and not surface ornamentation.