Question
x^3-5x^2+4x-20 > 0 interval notation
Answers
Reiny
factor by grouping
x^2(x-5) + 4(x-5) > 0
(x-5)(x^2+ 4) > 0
x^2 + 4 is always positive, so for the whole thing to be positive
x-5 > 0
x > 5
express it in the form you were taught.
x^2(x-5) + 4(x-5) > 0
(x-5)(x^2+ 4) > 0
x^2 + 4 is always positive, so for the whole thing to be positive
x-5 > 0
x > 5
express it in the form you were taught.