You can
put this solution on YOUR website!First you need to figure out where
. So, lets do this...
so either x=0 or
The second polynomial factorises futher to (2x-7)(2x-7) = 0, which means 2x = 7. In other words x = 7/2.
So there are 2 "roots" (where y=0): at x=0 and x=7/2.
The question asks where is the polynomial GREATER than zero. To answer this, you need to be able to sketch (not plot) the graph quickly. You need to know what a cubic looks like first and then apply that knowledge to the info you have.
The cubic looks like:
So, looking at the graph, where is the curve GREATER than zero? it is greater than zero when x>0 but not at the point x=7/2 --> here it is equal to zero.
So, answer is 0 < x < 7/2 and x > 7/2
OR x>0, but not x=7/2
Both say the same thing
jon.
