Diagram of simple filtration: oversize particles in the feed cannot pass through the lattice structure of the filter, while fluid and small particles pass through, becoming filtrate.
An odd function can be identified by replacing both the x and y values with -x and -y values. If the values in your equation are the opposite (positives are negatives and negatives are positives), then the function is odd. Take, for example, this equation y = x^2.
Increasing Functions. A function is increasing when the y-value increases as the x-value increases, like this: It is easy to see that y=f(x) tends to go up as it goes along.