Skip to main content

What is the integration of log (1+x^2)?

Use integration by part to solve this question.

\[% \color{red}{\boxed{\color{blue}{\boxed{\color{black}{\text{ Using integration by parts, we have}\\\displaystyle \quad \int \ln \left(1+x^{2}\right) d x\\\displaystyle =x \ln \left(1+x^{2}\right)-\int x \frac{2 x}{1+x^{2}} d x \\\displaystyle =x \ln \left(1+x^{2}\right)-2 \int\left(1-\frac{1}{1+x^{2}}\right) d x \\\displaystyle =x \ln \left(1+x^{2}\right)-2 x+2 \tan ^{-1} x+C}}}}} \]

Comments

Popular posts from this blog

Trigonometry Ratios and Identities - Notes, Concept and All Important Formula

TRIGONOMETRIC RATIOS & IDENTITIES Table Of Contents 1. RELATION BETWEEN SYSTEM OF MEASUREMENT OF ANGLES : \(\dfrac{D}{90}=\dfrac{G}{100}=\dfrac{2 C}{\pi}\) 1 Radian \(=\dfrac{180}{\pi}\) degree \(\approx 57^{\circ} 17^{\prime} 15^{\prime \prime}\) (approximately) 1 degree \(=\dfrac{\pi}{180}\) radian \(\approx 0.0175\) radian All Chapter Notes, Concept and Important Formula 2. BASIC TRIGONOMETRIC IDENTITIES : (a) \(\sin ^{2} \theta+\cos ^{2} \theta=1\) or \(\sin ^{2} \theta=1-\cos ^{2} \theta\) or \(\cos ^{2} \theta=1-\sin ^{2} \theta\) (b) \(\sec ^{2} \theta-\tan ^{2} \theta=1\) or \(\sec ^{2} \theta=1+\tan ^{2} \theta\) or \(\tan ^{2} \theta=\sec ^{2} \theta-1\) (c) If \(\sec \theta+\tan \theta\) \(=\mathrm{k} \Rightarrow \sec \theta-\tan \theta\) \(=\dfrac{1}{\mathrm{k}} \Rightarrow 2 \sec \theta\) \(=\mathrm{k}+\dfrac{1}{\mathrm{k}}\) (d) \(\operatorname{cosec}^{2} \theta-\cot ^{2} \theta=1\) or \(\operatorname{cosec}^{2} \theta=1+\cot ^{2} \th...

Straight Line - Notes, Concept and All Important Formula

STRAIGHT LINE Table Of Contents 1. RELATION BETWEEN CARTESIAN CO-ORDINATE & POLAR CO-ORDINATE SYSTEM If \((x, y)\) are Cartesian co-ordinates of a point \(P\) , then : \(x=r \cos \theta\) , \(y=r \sin \theta\) and \(r=\sqrt{x^{2}+y^{2}}, \quad \theta=\tan ^{-1}\left(\dfrac{y}{x}\right)\) All Chapter Notes, Concept and Important Formula 2. DISTANCE FORMULA AND ITS APPLICATIONS : If \(\mathrm{A}\left(\mathrm{x}_{1}, \mathrm{y}_{1}\right)\) and \(\mathrm{B}\left(\mathrm{x}_{2}, \mathrm{y}_{2}\right)\) are two points, then \(\mathbf{A B=\sqrt{\left(x_{2}-x_{1}\right)^{2}+\left(y_{2}-y_{1}\right)^{2}}}\) Note : (i) Three given points \(A, B\) and \(C\) are collinear, when sum of any two distances out of \(\mathrm{AB}, \mathrm{BC}, \mathrm{CA}\) is equal to the remaining third otherwise the points will be the vertices of triangle. (ii) Let \(A, B, C \& D\) be the four given points in a plane. Then the quadrilateral will be: (a) Square if \(A B=B C=C D=D...

Ellipse - Notes, Concept and All Important Formula

ELLIPSE 1. STANDARD EQUATION & DEFINITION : Standard equation of an ellipse referred to its principal axis along the co-ordinate axis is \(\dfrac{\mathbf{x}^{2}}{\mathbf{a}^{2}}+\dfrac{\mathbf{y}^{2}}{\mathbf{b}^{2}}=\mathbf{1}\) . where \(a>b \) & \( b^{2}=a^{2}\left(1-e^{2}\right)\) \(\Rightarrow a^{2}-b^{2}=a^{2} e^{2} .\) where \(e=\) eccentricity \((0<e<1)\) . \(\mathrm{FOCI}: \mathrm{S} \equiv(\mathrm{ae}, 0) \) & \( \mathrm{~S}^{\prime} \equiv(-\mathrm{ae}, 0) .\) (a) Equation of directrices : \(\mathrm{x}=\dfrac{\mathrm{a}}{\mathrm{e}} \) & \( \mathrm{x}=-\dfrac{\mathrm{a}}{\mathrm{e}} \text { . }\) (b) Vertices: \(\mathrm{A}^{\prime} \equiv(-\mathrm{a}, 0) \quad \) & \( \mathrm{~A} \equiv(\mathrm{a}, 0)\) (c) Major axis : The line segment \(A^{\prime} A\) in which the foci \(S^{\prime}\) & S lie is of length \(2 \mathrm{a} \) & \(\) is called the major axis \((a>b)\) of the ellipse. Point of intersection of major axis with dir...