Audio problem: When Cooke enters the motel room, the sound of the first hit that Matrix gives him happens a split second before the fist makes contact.
Revealing mistake: As Matrix's truck crashes at the bottom of the hill, you can see smoke coming out the tail pipe even though the truck is supposed to have been electrically sabotaged.
Continuity mistake: After Jenny is abducted and Matrix chases the bad guys, the windshield in his car swaps between very dirty and dusty in the wide angles to spotless in the close-ups.
Continuity mistake: The police van with Matrix inside pulls away from Cindy and drives for about 30 seconds including the fact that Cindy fired two rockets at it, and, yet, when it stops it is still much too close to where they began and this is even after someone misfired a rocket at them.
Continuity mistake: Matrix slams the caterpillar into the gun shop through the metal gates and continues for several seconds, it appears that the metal gates are knocked down a few times. Also, the caterpillar winds up very close to the window even after Matrix drives it for several seconds once inside.
Continuity mistake: When they arrive at the airport, Matrix closes the door of the car, and the window is almost closed. But, in the next shot, when Bennett says that he'll be ready, he is looking through a completely open window.
Other mistake: At the end when Matrix gets into the sea plane the the landing gear is down - the landing gear is for ground landing only. Also shown earlier in the film before Matrix starts his assault.
Continuity mistake: When Matrix leaves the plane rowing a boat there are two angles on Cindy: In the close-up her hair remains still, but in the wide angle there's a strong wind blowing it. This changes back and forth.
Continuity mistake: After the rocket-launcher scene Matrix's daughter is sitting on the floor with a wrinkled curtain at her feet. A shot later the curtain is less wrinkled.
Continuity mistake: When Arnold is crashing into the gun shop in the caterpillar you can see the camera to the rear (a black round one) and then also the camera at the front can be seen as a yellow box, attempting to be disguised as part of the engine block. These quickly disappear in subsequent shots.
Answer: They didn't know where Matrix lived. They were killing Matrix's old unit because they knew if they did General Kirby would make physical contact with Matrix to warn him. They simply followed Kirby to Matrix's home.
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