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.
In calculus, a function defined on a subset of the real numbers with real values is called monotonic if and only if it is either entirely increasing or decreasing. It is called monotonically increasing (also increasing or nondecreasing), if for all and such that one has, so preserves the order (see Figure 1). Likewise, a function is called monotonically decreasing (also decreasing or nonincreasing) if, whenever, then, so it reverses the order (see Figure 2).