I don't understand how do you get to , is there a general rule for that or you did by algebra? Further, I worked this out and I have 3b^2 < 16, not 4, did I do something wrong?
I don't understand how do you get to , is there a general rule for that or you did by algebra? Further, I worked this out and I have 3b^2 < 16, not 4, did I do something wrong?
Thanks.
Yes. I made a mistake it should be 3b^2 < 16. It is just the discrimant of the quadradic.