Now you probably know that the integral is x + a constant. Leaving out the constant is only "WRONG" in some hyper-pedantic high-school sense. Let us begin! The integral of a constant is equal to the constant times the integral's variable. Oh, and Euler, since every indefinite integral is "plus a constant," the constant is typically assumed to be there. Greetings! The following is a list of integrals (antiderivative functions) of rational functions.Any rational function can be integrated by partial fraction decomposition of the function into a sum of functions of the form: (−), and + ((−) +).which can then be integrated term by term. A party trick, perhaps. Here are some examples illustrating how to ask for an integral. Any expression multiplied by 1 is equal to itself. #color(blue)(int(du)/(1+u^2)=tan^-1u+C# #rarr# Where #u# is a function of #x#. By using this website, you agree to our Cookie Policy. You can think of dx as 1 * dx, so you are just integrating 1. Example 1. Learn more Accept. While I do believe Angad Kapoor has done justification to the mathematical manipulation involved, that is all I believe this is. As the integral that we are solving is an indefinite integral, when we finish integrating we must add the constant of integration C. This website uses cookies to ensure you get the best experience. #color(red)("Proof:")# #int(du)/(1+u^2)# Integration by Trigonometric Substitution. Integral of 1. integrate x/(x-1) integrate x sin(x^2) integrate x sqrt(1-sqrt(x)) integrate x/(x+1)^3 from 0 to infinity; integrate 1/(cos(x)+2) from 0 to 2pi; integrate x^2 sin y dx dy, x=0 to 1, y=0 to pi; View more examples » Access instant learning tools. For other types of functions, see lists of integrals Free double integrals calculator - solve double integrals step-by-step. Learn how to solve integrals of polynomial functions problems step by step online. Integral of csc x $$\int \csc x \ dx$$ The cosecan integral can be deduced if you know some derivation formulas, then we will see how to get to the result of $-\log \left(\cot u+\csc u \right)$ with the derivative formulas.