Group terms: Group terms to find common factors.Group the first two terms and the last two terms separately.15u3+20u2−3u−4 can be written as (15u3+20u2)+(−3u−4).
Factor common terms: Factor out the greatest common factor from each group.From the first group 15u3+20u2, we can factor out 5u2, giving us 5u2(3u+4).From the second group −3u−4, we can factor out −1, giving us −1(3u+4).Now we have 5u2(3u+4)−1(3u+4).
Factor binomial: Factor out the common binomial factor.Both groups contain the common factor (3u+4).Factor out (3u+4) from both groups.This gives us (3u+4)(5u2−1).
Factor difference of squares: Factor the difference of squares if possible.The second term 5u2−1 is a difference of squares and can be factored further.5u2−1 can be written as (5u)2−(1)2, which is a difference of squares.Factoring this gives us (5u−1)(5u+1).
Write final form: Write the final factored form. Combine the factored terms to get the final factored form of the original polynomial. The final factored form is (3u+4)(5u−1)(5u+1).