What is the integral of 3/((1+9x^2)^{3/2)} ?

The integral of 3/((1+9x^2)^{3/2)} is (3x)/((1+9x^2)^{1/2)}+C

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integral of 3/((1+9x^2)^{3/2)}

\int \frac{3}{( 1 + 9 x ^{2} ) ^{\frac{3}{2}}} d x

\frac{3 x}{( 1 + 9 x ^{2} ) ^{\frac{1}{2}}} + C

Solution steps

\int \frac{3}{( 1 + 9 x ^{2} ) ^{\frac{3}{2}}} d x

Take the constant out:

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

= 3 \cdot \int \frac{1}{( 1 + 9 x ^{2} ) ^{\frac{3}{2}}} d x

Apply Trigonometric Substitution

= 3 \cdot \int \frac{1}{3 sec ( u )} d u

Take the constant out:

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

= 3 \cdot \frac{1}{3} \cdot \int \frac{1}{sec ( u )} d u

Rewrite using trig identities

= 3 \cdot \frac{1}{3} \cdot \int cos (u) d u

Use the common integral:

\int cos (u) d u = sin (u)

= 3 \cdot \frac{1}{3} sin (u)

Substitute back

u = arctan (3 x)

= 3 \cdot \frac{1}{3} sin (arctan (3 x))

Simplify

3 \cdot \frac{1}{3} sin (arctan (3 x)) : \frac{3 x}{( 1 + 9 x ^{2} ) ^{\frac{1}{2}}}

= \frac{3 x}{( 1 + 9 x ^{2} ) ^{\frac{1}{2}}}

Add a constant to the solution

= \frac{3 x}{( 1 + 9 x ^{2} ) ^{\frac{1}{2}}} + C

What is the integral of 3/((1+9x^2)^{3/2)} ?
The integral of 3/((1+9x^2)^{3/2)} is (3x)/((1+9x^2)^{1/2)}+C