Question
Evaluate the following intregals:
$\int\frac{\text{x}^2+6\text{x}-8}{\text{x}^3-4\text{x}}\ \text{dx}$

Answer

Let $\text{I}=\int\frac{\text{x}^2+6\text{x}-8}{\text{x}^3-4\text{x}}\ \text{dx}$ $\Rightarrow\text{I}=\int\frac{\text{x}^2+6\text{x}-8}{\text{x}(\text{x}+2)(\text{x}-2)}\text{ dx}$Now,
Let $\frac{\text{x}^2+6\text{x}-8}{\text{x}(\text{x}+2)(\text{x}-2)}=\frac{\text{A}}{\text{x}}+\frac{\text{B}}{\text{x}+2}+\frac{\text{C}}{\text{x}-2}$
$\Rightarrow\text{x}^2+6\text{x}-8=\text{A}(\text{x}^2-4)+\text{B}(\text{x}-2)\text{x}+\text{C}(\text{x}+2)\text{x}$ Put x = 0 ⇒ -8 = -4A ⇒ A = 2 Put x = -2 ⇒ -16 = 8B ⇒ B = -2 Put x = 2 ⇒ 8 = 8C ⇒ C = 1 Thus,$\text{I}=\int\frac{2\text{dx}}{\text{x}}-\int\frac{2\text{dx}}{\text{x}+2}+\int\frac{\text{dx}}{\text{x}-2}$
$=2\log|\text{x}|-2\log|\text{x}+2|+\log|\text{x}-2|+\text{C}$
$\therefore\text{I}=\log\Big|\frac{\text{x}^2(\text{x}-2)}{(\text{x}+2)^2}\Big|+\text{C}$

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

Evaluate the following intregals:
$\int\frac{1}{2+\sin\text{x}+\cos\text{x}}\text{dx}$
Find $\frac{\text{dy}}{\text{dx}}$
$\text{y}=\text{x}^{\sin\text{x}}+\big(\sin\text{x}\big)^\text{x}$
If $\text{y}=\sin^{-1}\Big(\frac{2\text{x}}{1+\text{x}^2}\Big)+\sec^{-1}\Big(\frac{1+\text{x}^2}{1-\text{x}^2}\Big), 0<\text{x}<1$ prove that $\frac{\text{dy}}{\text{dx}}=\frac{4}{1+\text{x}^2}$
Find the points on the curve $x^2 + y^2 - 2x - 3 = 0$ at which the tangents are parallel to the x-axis.
A man owns a field of area 1000 sq.m. He wants to plant fruit trees in it. He has a sum of Rs. 1400 to purchase young trees. He has the choice of two types of trees. Type A requires 10 sq.m of ground per tree and costs Rs. 20 per tree and type B requires 20 sq.m of ground per tree and costs Rs. 25 per tree. When fully grown, type A produces an average of 20kg of fruit which can be sold at a profit of Rs. 2.00 per kg and type B produces an average of 40kg of fruit which can be sold at a profit of Rs. 1.50 per kg. How many of each type should be planted to achieve maximum profit when the trees are fully grown? What is the maximum profit?
A company sells two different products A and B. The two products are produced in a common production process and are sold in two different markets. The production process has a total capacity of 45000 man-hours. It takes 5 hours to produce a unit of A and 3 hours to produce a unit of B. The market has been surveyed and company officials feel that the maximum number of units of A that can be sold is 7000 and that of B is 10,000. If the profit is Rs. 60 per unit for the product A and Rs. 40 per unit for the product B, how many units of each product should be sold to maximize profit? Formulate the problem as LPP.
If $\text{A}=\begin{bmatrix}3&2&0\\1&4&0\\0&0&5\end{bmatrix},$ show that $A^2 - 7A + 10I_3 = 0.$
Evaluate : $\int \frac{\tan \theta+\tan ^3 \theta}{1+\tan ^3 \theta} \cdot d \theta$
Find the points on the curve $y = x^3 - 2x^2 - 2x$ at which the tangent lines are parallel to the line $y = 2x - 3.$
One bag contains $4$ yellow and $5$ red balls. Another bag contains $6$ yellow and $3$ red balls. A ball is transferred from the first bag to the second bag and then a ball is drawn from the second bag. Find the probability that ball drawn is yellow.