According to Weinsstein, "An integral is a mathematical object that can be interpreted as an area or a generalization of area."[1] Integration is a process of computing an integral.
How to integrate a function
Generally, this is the expression of integral:
where f(x) is a function for x. This function of x is surounded by integral's symbol and dx.
This can be solved this way:
If we suppose the function is x2+5, a is 2, b is 1, the integral can be solved by:
We know the value of a and b of the integral before calculation, so this called definite integral.
What if we don't know the value of a and b?
where C is a Constant number like 1, 4, 7, 20, 100, 1.5, 1/3... whatever number as long as it is constant.
This is called indefinite integral.
[1] WolframMathworld. http://mathworld.wolfram.com/Integral.html 21 March 2018 visited.
