Question Bank [2022] — Maths STD 12 Science — Question
Maharashtra BoardEnglish MediumSTD 12 ScienceMathsQuestion Bank [2022]2 Marks
Question
$\int e ^{3 \log x}\left(x^4+1\right)^{-1} d x$
✓
Answer
$ \text { Let } I =\int e ^{3 \log x}\left(x^4+1\right)^{-1} d x$
$=\int \frac{ e ^{\log \left(x^3\right)}}{x^4+1} d x$
$=\int \frac{x^3}{x^4+1} d x $
Put $x^4+1=t$
Differentiating w.r.t. $x$, we get
$ 4 x ^3 dx = dt$
$\therefore x ^3 dx =\frac{1}{4} dt$
$\therefore I =\frac{1}{4} \int \frac{ dt }{ t }$
$=\frac{1}{4} \log | t |+ c$
$\therefore I =\frac{1}{4} \log \left|x^4+1\right|+ c $
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.