How do you solve the following Quadratic Inequality #x^2+2x-15<0#?
The solution is
There are more than one ways to solve this inequality.
The product of two real numbers can be negative if one of them is positive and another is negative.
Therefore, we have two solutions:
So, the solution is
As we know, the graph of the quadratic polynomial on the left is parabola. Since the coefficient at
Therefore, the only way it can be negative is in-between its roots, where it's equal to zero.
In other words, the solutions to a inequality is the area between solutions to equality
Obvious solutions are
So, the solutions are