Posted by ladybug on Saturday, September 29, 2012 at 11:29pm.
solve the the following inequality. write your solution in interval notation.
x^349x<0
_ (I don't know how to make the sign on my computer)

precalculus  Reiny, Sunday, September 30, 2012 at 8:12am
x^3  49x < 0
x(x^2  49) < 0
x(x+7)(x7) < 0
consider f(x) = x(x+7)(x7)
the xintercepts would be 7, 0, 7
Knowing the basic shape of a cubic, we have
x < 7 OR 0 < x < 7
I will let you write that in the interval notation that you learned.