Advice 1: How to find the zeros of the function

The mathematical concept of a function clearly shows how one value completely determines the value of the other variable. Usually deals with numeric functions that are put in the corresponding one of the other numbers. A zero of a function, usually called the value of the argument at which the function becomes zero.
How to find the zeros of the function
In order to find the zeros of the function, it is necessary to equate the right side to zero and solve the resulting equation. Suppose you are given a function f(x)=x-5.
To find the zeros of this function, we equate the right side to zero: x-5=0.
Solving this equation will get x=5 and this value argument and is null function. That is, when the value of argument 5, the function f(x) vanishes.
When finding roots of an equation may be extra roots. It is easy to check: simply substitute the obtained value of the argument to the function and verify whether the function to zero.
Useful advice
Sometimes the function can not be expressed in explicit form using your argument, then you just need to know what is this function. An example of this is the equation of the circle.

Advice 2: How to find the value of the function

The notion of function in mathematics understand the relationship between the elements of sets. More precisely, it is "law" by which each element of one set (called the domain) corresponds to an element of another set (called the range).
How to find the value of the function
You will need
  • Knowledge in the field of algebra and mathematical analysis.
The value function is a realm of values which a function can take. For example, the values of the function f(x)=|x| from 0 to infinity. To find the value of the function at a particular point, you need to substitute the argument of a function to its numeric equivalent, the resulting number will be the value ofm functions. Let given the function f(x)=|x| - 10 + 4x. Find the value of the function at the point x=-2. Substitute instead of x the number -2: f(-2)=|-2| - 10 + 4*(-2) = 2 - 10 - 8 = -16. That is, the value of the function at the point -2 -16.
Before looking for the value of the function at the point - make sure it is in the domain of the function.
Useful advice
Similarly, you can find the value of a function of several arguments. The difference is that instead of a single number, you will need to substitute a few - the number of function arguments.
Is the advice useful?