Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section A

Chapter

Determinants

Question:

$\int e^{2 x^3+2 \log _{e} x} dx=$

Options:

$\frac{1}{3} e^{2 x^3}+C$

$\frac{1}{6} e^{2 x^3}+C$

$\frac{1}{2} e^{2 x^3}+C$

$\frac{1}{12} e^{2 x^3}+C$

Correct Answer:

$\frac{1}{6} e^{2 x^3}+C$

Explanation:

$I =\int e^{2 x^3+2 \log x} d x$

$=\int e^{2 x^3} e^{2 \log x} d x$

$=\int e^{2 x^3} e^{\log x^2} d x$

$I =\int x^2 e^{2 x^3} d x$

so let $z = 2x^3$

$dz = 6x^2 dx$

$\frac{dz}{6}=x^2dz$

so $I = \int \frac{e^z}{6}dz$

$\frac{e^z}{6}+C$

$\frac{e^{2 x^3}}{6}+C$