Find the product of all positive integer values of $c$ such that $8x^2+15x+c=0$ has two real roots.
5040. Since in order for it to be real, in the quadractic formula, b^2-4ac>0.
Here 225-32c>0. 225>32c. 225/32>c.
225/32>7 and <8 so the answer should be 7!.
7!=5040.
