MCQ
$\int {} $ $e^{\tan \theta} $ $(\sec \theta - \sin \theta )$ $ d\theta $ equals :
  • A
    $- e^{\tan \theta} \sin \theta + c$
  • B
    $e^{\tan \theta}\sin \theta + c$
  • C
    $e^{\tan \theta } \sec \theta + c$
  • $e^{\tan \theta} \cos \theta + c$

Answer

Correct option: D.
$e^{\tan \theta} \cos \theta + c$
d
Let $I=\int e^{\tan \theta}(\sec \theta-\sec \theta) d \theta$

Substitute $\tan \theta=t \Rightarrow \sec ^{2} \theta d \theta=d t$

$\therefore I=\int e^{t}(\cos \theta-\tan \theta \sec \theta) d t$

$=\int e^{t}\left(\frac{1}{\sqrt{1+t^{2}}}-t \sqrt{1+t^{2}}\right) d t$

As $\frac{d}{d x}\left(\frac{1}{\sqrt{1+t^{2}}}\right)=t \sqrt{1+t^{2}}$

$\therefore I=e^{t}\left(\frac{1}{\sqrt{1+t^{2}}}\right)=e^{\tan \theta} \cos \theta+c$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions