English

Integrate the function: 1x-x3

Advertisements
Advertisements

Question

Integrate the function:

`1/(x - x^3)`

Sum
Advertisements

Solution

Let `1/(x - x^3) = 1/(x(1 + x)(1 - x))`

`≡ A/x + B/(1 + x) + C/(1 - x)`

⇒ 1 = A (1 + x) (1 – x) + Bx (1 – x) + Cx (1 + x)        …(1)

Putting x = 0 in equation (1),

1 = A(1 + 0) (1 – 0)

⇒ A = 1

Putting x = -1 in equation (1),

1 = B (-1) (1 + 1)

`=> B = - 1/2`

Putting x = 1 in equation (1),

1 = C(1)(1 + 1)

`=> C = 1/2`

`therefore 1/(x - x^3) = 1/x - 1/(2(1 + x)) + 1/(2(1 - x))`

`therefore int 1/(x - x^3) dx = int 1/x dx - 1/2 int 1/(1 + x) dx + 1/2 int 1/(1 - x) dx`

`= log |x| - 1/2 log |1 + x| - 1/2 log |1 - x| + C`

`= 1/2 log |x|^2 - 1/2 log |1 - x^2| + C`

`= 1/2 log |x^2/(1 - x^2)|` +  C

shaalaa.com
  Is there an error in this question or solution?
Chapter 7: Integrals - Exercise 7.12 [Page 352]

APPEARS IN

NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 7 Integrals
Exercise 7.12 | Q 1 | Page 352

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

If `f(x) =∫_0^xt sin t dt` , then write the value of f ' (x).


Find an anti derivative (or integral) of the following function by the method of inspection.

(axe + b)2


Find the following integrals:

`intx^2 (1 - 1/x^2)dx`


Find the following integrals:

`int(2x^2 + e^x)dx`


Find the following integrals:

`int (x^3 + 3x + 4)/sqrtx dx`


Find the following integrals:

`int(1 - x) sqrtx dx`


Find the following integrals:

`int(2x^2 - 3sinx + 5sqrtx) dx`


Find the following integrals:

`int(sec^2x)/(cosec^2x) dx`


Find the following integrals:

`int (2 - 3 sinx)/(cos^2 x) dx.`


The anti derivative of `(sqrtx + 1/ sqrtx)` equals:


Integrate the function:

`1/(xsqrt(ax - x^2)) ["Hint : Put x" = a/t]`


Integrate the function:

`(5x)/((x+1)(x^2 +9))`


Integrate the function:

`sinx/(sin (x - a))`


Integrate the function:

`cos x/sqrt(4 - sin^2 x)`


Integrate the function:

`(sin^8 x - cos^8 x)/(1-2sin^2 x cos^2 x)`


Integrate the function:

`1/((x^2 + 1)(x^2 + 4))`


Integrate the function:

`cos^3 xe^(log sinx)`


Integrate the function:

`sqrt((1-sqrtx)/(1+sqrtx))`


Integrate the function:

`(x^2 + x + 1)/((x + 1)^2 (x + 2))`


Evaluate `int tan^(-1) sqrtx dx`


Find : \[\int\frac{\left( x^2 + 1 \right)\left( x^2 + 4 \right)}{\left( x^2 + 3 \right)\left( x^2 - 5 \right)}dx\] .


Evaluate: `int  (1 - cos x)/(cos x(1 + cos x))  dx`


The anti derivative of `(sqrt(x) + 1/sqrt(x))` is equals:


`sqrt((10x^9 + 10^x  log e^10)/(x^10 + 10^x)) dx` equals


`int (dx)/(sin^2x cos^2x) dx` equals


`int (xdx)/((x - 1)(x - 2))` equals


`int x^2 e^(x^3) dx` equals


`int sqrt(x^2 - 8x + 7)  dx` is equal to:-


What is anti derivative of `e^(2x)`


If the normal to the curve y(x) = `int_0^x(2t^2 - 15t + 10)dt` at a point (a, b) is parallel to the line x + 3y = –5, a > 1, then the value of |a + 6b| is equal to ______.


`d/(dx)x^(logx)` = ______.


Anti-derivative of `(tanx - 1)/(tanx + 1)` with respect to x is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×