Here, we show you a step-by-step solved example of integration by trigonometric substitution. This solution was automatically generated by our smart calculator:
We can solve the integral $\int\sqrtdx$ by applying integration method of trigonometric substitution using the substitution
$x=2\tan\left(\theta \right)$ Intermediate steps
Differentiate both sides of the equation $x=2\tan\left(\theta \right)$
$dx=\fracFind the derivative
$\fracThe derivative of a function multiplied by a constant is equal to the constant times the derivative of the function
$2\fracThe derivative of the tangent of a function is equal to secant squared of that function times the derivative of that function, in other words, if $$, then $$
$2\fracThe derivative of the linear function is equal to $1$
$2\sec\left(\theta \right)^2$Now, in order to rewrite $d\theta$ in terms of $dx$, we need to find the derivative of $x$. We need to calculate $dx$, we can do that by deriving the equation above
$dx=2\sec\left(\theta \right)^2d\theta$ Explain this step further Intermediate steps
The power of a product is equal to the product of it's factors raised to the same power
$\int2\sqrt<4\tan\left(\theta \right)^2+4>\sec\left(\theta \right)^2d\theta$Simplify $4\tan\left(\theta \right)^2+4$ into secant function
$\int2\sqrt<4\sec\left(\theta \right)^2>\sec\left(\theta \right)^2d\theta$The power of a product is equal to the product of it's factors raised to the same power
$\int2\cdot 2\sec\left(\theta \right)\sec\left(\theta \right)^2d\theta$Multiply $2$ times $2$
$\int4\sec\left(\theta \right)\sec\left(\theta \right)^2d\theta$When multiplying exponents with same base you can add the exponents: $4\sec\left(\theta \right)\sec\left(\theta \right)^2$
$\int4\sec\left(\theta \right)^<3>d\theta$3>Substituting in the original integral, we get
$\int4\sec\left(\theta \right)^<3>d\theta$3> Explain this step furtherThe integral of a function times a constant ($4$) is equal to the constant times the integral of the function
$4\int\sec\left(\theta \right)^<3>d\theta$3> Intermediate steps
Simplify the integral $\int\sec\left(\theta \right)^d\theta$ applying the reduction formula, $\displaystyle\int\sec(x)^dx=\frac>+\frac\int\sec(x)^dx$
$4\left(\frac<\sin\left(\theta \right)\sec\left(\theta \right)^>+\frac\int\sec\left(\theta \right)^d\theta\right)$Subtract the values $3$ and $-1$
$4\left(\frac<\sin\left(\theta \right)\sec\left(\theta \right)^<2>>+\frac\int\sec\left(\theta \right)^d\theta\right)$Subtract the values $3$ and $-1$
$4\left(\frac<\sin\left(\theta \right)\sec\left(\theta \right)^>+\frac\int\sec\left(\theta \right)^d\theta\right)$Subtract the values $3$ and $-1$
$4\left(\frac<\sin\left(\theta \right)\sec\left(\theta \right)^>+\frac\int\sec\left(\theta \right)^d\theta\right)$Subtract the values $3$ and $-2$
$4\left(\frac<\sin\left(\theta \right)\sec\left(\theta \right)^>+\frac\int\sec\left(\theta \right)^d\theta\right)$Subtract the values $3$ and $-2$
$4\left(\frac<\sin\left(\theta \right)\sec\left(\theta \right)^>+\frac\int\sec\left(\theta \right)^d\theta\right)$Simplify the integral $\int\sec\left(\theta \right)^d\theta$ applying the reduction formula, $\displaystyle\int\sec(x)^dx=\frac>+\frac\int\sec(x)^dx$
$4\left(\frac<\sin\left(\theta \right)\sec\left(\theta \right)^>+\frac\int\sec\left(\theta \right)^d\theta\right)$ Explain this step further Intermediate steps
$4\left(\frac<\sin\left(\theta \right)\sec\left(\theta \right)^>\right)+4\cdot \left(\frac\right)\int\sec\left(\theta \right)^d\theta$Any expression to the power of $1$ is equal to that same expression
$4\left(\frac<\sin\left(\theta \right)\sec\left(\theta \right)^>\right)+4\cdot \left(\frac\right)\int\sec\left(\theta \right)d\theta$Multiply the fraction and term in $4\cdot \left(\frac\right)\int\sec\left(\theta \right)d\theta$
$4\left(\frac<\sin\left(\theta \right)\sec\left(\theta \right)^>\right)+\frac\int\sec\left(\theta \right)d\theta$Any expression multiplied by $1$ is equal to itself