The 9400M supports a resolution of up to 2560 x 1600 for external displays, which can be read on the technical specifications page of the MBP.
I'm too lazy too for giving you the link though.
Also your HD TV will have a maximum resolution of 1920 x 1080, so you're in the clear. Screen size is independent of resolution in regards with HD TVs anyway.
PS:
HD - High Definition
TV - TeleVision
HDD - Hard Disk Drive
but sometimes HD is used to mean HDD, therefore your thread title is a bit confusing, especially with the term "external" in it. You could add "TV" for example to be more specific.