factor completely?

Question

3u^2 - 3t^4 u^2

Answer 1

3u^2(1-t^4)
=3u^2(1-t^2)(1+t^2)
=3u^2(1-t)(1+t)(1+t^2)

Answer 2

3u² - 3t^4 u² =
3u²(1 - t^4) =
3u²(1 - t²)(1 + t²)
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Answer 3

3U2 - 3T4U2
Factored completely is -3u^2(T^4). Hope this helps.