quasi wrote: > punisher wrote: >> >> Can someone help me solve this >> >> Find the largest values of the integer a for which ax^2-5x-3 is >> negative for all values of x. > > Is it homework? > > I'll give a few hints: > > (1) Can the required value of a be positive? Can it be zero? > > (2) Can you find the vertex coordinates in terms of a? > > (3) As an alternative to (2), find the discriminant in > terms of a. How can it help? > > quasi
A more general hint: if it's homework then there is a good chance that what was done most recently in the classroom or read most recently in the textbook will be relevant. So if one is stumped by a homework question look first at what was (supposed to be) most recently learned.
(Mind you, if I were a teacher I'd always throw in a few homework questions relevant to what I taught six months previously...)
-- ...if someone seduced my daughter it would be damaging and horrifying but not fatal. She would recover, marry and have lots of children... On the other hand, if some elderly, or not so elderly, schoolmaster seduced one of my sons and taught him to be a homosexual, he would ruin him for life. That is the fundamental distinction. -- Lord Longford