What is the integral of sqrt(x^2+16) ?

The integral of sqrt(x^2+16) is 16(1/32 xsqrt(16+x^2)+1/2 ln((|x+sqrt(16+x^2)|)/4))+C

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

integral of sqrt(x^2+16)

\int x^{2} + 16 d x

16 (\frac{1}{32} x 16 + x^{2} + \frac{1}{2} ln (\frac{x + 16 + x ^{2}}{4})) + C

Solution steps

\int x^{2} + 16 d x

Apply Trigonometric Substitution

= \int 16 sec^{3} (u) d u

Take the constant out:

\int a \cdot f (x) d x = a \cdot \int f (x) d x

= 16 \cdot \int sec^{3} (u) d u

Apply Integral Reduction

= 16 (\frac{sec ^{2} ( u ) sin ( u )}{2} + \frac{1}{2} \cdot \int sec (u) d u)

\int sec (u) d u = ln ∣ tan (u) + sec (u) ∣

= 16 (\frac{sec ^{2} ( u ) sin ( u )}{2} + \frac{1}{2} ln ∣ tan (u) + sec (u) ∣)

Substitute back

u = arctan (\frac{1}{4} x)

= 16 (\frac{sec ^{2} ( arctan ( \frac{1}{4} x ) ) sin ( arctan ( \frac{1}{4} x ) )}{2} + \frac{1}{2} ln tan (arctan (\frac{1}{4} x)) + sec (arctan (\frac{1}{4} x)))

Simplify

16 (\frac{sec ^{2} ( arctan ( \frac{1}{4} x ) ) sin ( arctan ( \frac{1}{4} x ) )}{2} + \frac{1}{2} ln tan (arctan (\frac{1}{4} x)) + sec (arctan (\frac{1}{4} x))) : 16 (\frac{1}{32} x 16 + x^{2} + \frac{1}{2} ln (\frac{x + 16 + x ^{2}}{4}))

= 16 (\frac{1}{32} x 16 + x^{2} + \frac{1}{2} ln (\frac{x + 16 + x ^{2}}{4}))

Add a constant to the solution

= 16 (\frac{1}{32} x 16 + x^{2} + \frac{1}{2} ln (\frac{x + 16 + x ^{2}}{4})) + C

What is the integral of sqrt(x^2+16) ?
The integral of sqrt(x^2+16) is 16(1/32 xsqrt(16+x^2)+1/2 ln((|x+sqrt(16+x^2)|)/4))+C