3x2 - Dragon Ball Z: Dragon Box

Goku arrives and stands before Freeza. Vegeta, seeing the level to which Goku has powered up, declares to Freeza "this is a Super Saiyan." But in that instant, Freeza's beam runs through Vegeta's heart! Trusting in Goku's abilities, Vegeta pins his Saiyan pride on him, and then perishes. Goku digs a grave for Vegeta, and then his anger toward Freeza explodes.