हिंदी

Evaluate: ∫-111+x29-x2 dx - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

Evaluate: `int_(-1)^1 (1 + x^2)/(9 - x^2)  "d"x`

योग

उत्तर

Let I = `int_(-1)^1 (1 + x^2)/(9 - x^2)  "d"x`

∴ I = `int_(-1)^1  1/(9 - x^2)  "d"x + int_(-1)^1  x^3/(9 - x^2)  "d"x`

= I1 + I2  ...(say)     ......(i)

Let `"f"(x) = 1/(9 - x^2)`

∴ f(−x) = `1/(9 - (- x)^2`

= `1/(9 - x^2)`

= f(x)

∴ f(x) is an even function.

∴ I1 = `int_(-1)^1 1/(9 - x^2)  "d"x`

= `2 int_0^1  1/(9 - x^2)  "d"x`

= `2 int_0^1 1/(3^2 - x^2)  "d"x`

= `2[1/(2 xx 3)* log|(3 + x)/(3 - x)|]_0^1`

= `1/3[log(4/2) - log(1)]`

∴ I1 = `1/3 log 2`

Let g(x) = `x^3/(9 - x^2)`

∴ g(−x) = `(-x)^3/(9 - (- x)^2` 

= `(-x^3)/(9 - x^2)`

= − g(x)

∴ g (x) is an odd function.

∴ I2 = `int_(-1)^1 x^3/(9 - x^2)  "d"x` = 0

From (i), we get

I = I1 + I2 

∴ I = `1/3 log 2 + 0`

∴ I = `1/3 log 2`

shaalaa.com
Methods of Evaluation and Properties of Definite Integral
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 2.4: Definite Integration - Long Answers III

संबंधित प्रश्न

Evaluate: `int_0^1 (x^2 - 2)/(x^2 + 1).dx`


Evaluate: `int_0^oo xe^-x.dx`


Evaluate the following:

`int_0^a (1)/(x + sqrt(a^2 - x^2)).dx`


If `int_0^1 ("d"x)/(sqrt(1 + x) - sqrt(x)) = "k"/3`, then k is equal to ______.


`int_0^1 (x^2 - 2)/(x^2 + 1)  "d"x` =


`int_0^(pi/2) log(tanx)  "d"x` =


Evaluate: `int_0^(pi/4) sec^2 x  "d"x`


Evaluate: `int_0^1 |x|  "d"x`


Evaluate: `int_0^1 1/sqrt(1 - x^2)  "d"x`


Evaluate: `int_0^(pi/2)  (sin2x)/(1 +  sin^2x)  "d"x`


Evaluate: `int_0^(pi/2) sqrt(1 - cos 4x)  "d"x`


Evaluate: `int_0^(pi/4) (tan^3x)/(1 + cos 2x)  "d"x`


Evaluate: `int_1^3 (cos(logx))/x  "d"x`


Evaluate: `int_0^(pi/2) (sin^2x)/(1 + cos x)^2 "d"x`


Evaluate: `int_0^9 sqrt(x)/(sqrt(x) + sqrt(9 - x)  "d"x`


Evaluate: `int_3^8 (11 - x)^2/(x^2 + (11 - x)^2)  "d"x`


Evaluate: `int_0^1 x* tan^-1x  "d"x`


Evaluate: `int_0^(pi/4) sec^4x  "d"x`


Evaluate: `int_0^(pi/4)  (sec^2x)/(3tan^2x + 4tan x + 1)  "d"x`


Evaluate: `int_0^pi x*sinx*cos^2x* "d"x`


Evaluate: `int_0^(pi/4) log(1 + tanx)  "d"x`


Evaluate: `int_0^(π/4) sec^4 x  dx`


`int_0^(π/2) sin^6x cos^2x.dx` = ______.


If `int_2^e [1/logx - 1/(logx)^2].dx = a + b/log2`, then ______.


Evaluate: `int_0^1 tan^-1(x/sqrt(1 - x^2))dx`.


Evaluate:

`int_(-π/2)^(π/2) |sinx|dx`


Evaluate:

`int_(π/6)^(π/3) (root(3)(sinx))/(root(3)(sinx) + root(3)(cosx))dx`


Evaluate:

`int_0^(π/2) (sin 2x)/(1 + sin^4x)dx`


`int_0^1 x^2/(1 + x^2)dx` = ______.


Find the value of ‘a’ if `int_2^a (x + 1)dx = 7/2`


Prove that: `int_0^1 logx/sqrt(1 - x^2)dx = π/2 log(1/2)`


Evaluate `int_(-π/2)^(π/2) sinx/(1 + cos^2x)dx`


If `int_0^π f(sinx)dx = kint_0^π f(sinx)dx`, then find the value of k.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×