How to solve indefinite integral of one divided by x rise to four by dx ?

Short answer: indefinite integral of one divided by x rise to four by dx is (-1/3x^3)+C. ∫ (1/x^4)dx is not particulary hard integral. You can solve it in 6 easy steps. We will walk you through and explain everything. Let's start.

how to solve indefinite integral of one divided by x rise to four by dx

Table of contents

Required assumtions

Usually, we have some additional info about function f of (x). In our case:

  1. f(x) belongs to real numbers
  2. f(x) is integrable in that domain
assumtions for indefinite integral of one divided by x rise to four by dx

 

Step by step solution of ∫ (1/x^4)dx

We will solve ∫ (1/x^4)dx in 6 easy steps. Let's get started

Step 1

From symbol dx we know that differential of variable x indicates that the variable of integration is x. Let’s rewrite integrand - function inside the integral without fraction- knowing that 1 divided by u is equal to u rise to -1. In our case u is equal to x.

step 1

Step 2

We may swap 1 divided by x rise to four with x rise to minus four. Then we may directly use the formula, which says integral of u rise to n by du is equal to u rise to n+1 divided by n+1. In our case n is equal to -4.

step 2

Step 3

Thus, we have x rise to minus 4 plus 1 divided by minus four plus one. We must also add constant C belonging to the set of real numbers because our solution is not a single function but a whole class of functions.

step 3

Step 4

So, we have x rise to -3 divided by -3. To make it smoother we can modify further the equation by moving minus from denominator to the numerator. It will not affect our equation.

step 4

Step 5

We can express it as -1 multiplied by x rise to -3 as there is no difference if we have minus next to x rise to -3 or we change it into -1 as it is not changing our final result. Also, we may get rid of minus in x rise to -3. Remembering that u rise to -n is equal to one divided by u rise to n. In our case u=x and n=3.

step 5

Step 6

And we leave only -1 in numerator and move x rise to 3 to denominator.

step 6

 

What is indefinite integral of one divided by x rise to four by dx?

We finally did it: ∫ (1/x^4)dx =(-1/3x^3)+C

(1/x^4)dx =(-1/3x^3)+C

Full video of how to solve ∫ (1/x^4)dx

Dictionary

Integration (antidifferentiation)

Computation (process of finding) of an integral, opposite process to differentiation.

Integrand

Function placed between sign of integral and differential of variable of integration e.g. $${{ \int f(x)dx}}$$,
where:
$${{ \int }}$$- integration operator,
f(x) – integrand,
dx- differential of variable of integration x

Integrable function

Function that integral over its domain is finite.

Indefinite integral

Represents a class of primitive functions whose derivative is the integrand e.g. $${{\int f(x)dx=F(x)+C \Leftrightarrow F’(x)=f(x)}}$$
$${{C=const. }}$$,
$${{f, F,C \in R }}$$
R-real numbers
$${{\int f(x)dx}}$$ - indefinite integral of function f(x) by dx,
$${{F(x)+C}}$$ – a class of primitive functions that $${{F’(x)=f(x) }}$$,
F(x) - primitive function, usually written in capital letters,
R-real numbers.

Function

Function specified on a set X and having values in set Y is an assignment each element of set X specifically one element in set Y.
$${{f: X \rightarrow Y}}$$
f-function name,
X-set of elements of function f, domain of a function f
Y-set of function values of function f, codomain of a function f
$${{x\in X, y \in Y}}$$
$${{y=f(x) f: x\rightarrow y}}$$
$${{y=y(x), }}$$
y(x)-vales of the function named y,
x-independent variable,
y-dependent variable.