हिंदी

∫xcos3x dx - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

`int xcos^3x  "d"x`

योग
Advertisements

उत्तर

Let I = `int xcos^3x  "d"x`

cos3x = 4cos3x − 3cosx

∴ 4cos3x = 3cos x + cos 3x

∴ cos3x = `1/4 (3cos x + cos 3x)`

∴ I = `1/4 int x (3cos x + cos 3x)  "d"x`

= `1/4[x int (3cosx + cos3x) "d"x - int{"d"/("d"x)(x) int(3cos x + cos 3x)"d"x}"d"x]`

= `1/4[x(3sinx + (sin3x)/3) - int 1(3sinx + (sin3x)/3)"d"x]`

= `1/4[3x sinx + x/3 sin 3x - (-3 cosx - 1/3 * (cos3x)/3)] + "c"`

∴ I = `1/4(3x sinx + x/3 sin 3x + 3 cos x + 1/9 cos 3x) + "c"`

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 2.3: Indefinite Integration - Long Answers III

वीडियो ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्न

Find : `int x^2/(x^4+x^2-2) dx`


Evaluate:

`int x^2/(x^4+x^2-2)dx`


Find: `I=intdx/(sinx+sin2x)`


Integrate the rational function:

`x/((x-1)(x- 2)(x - 3))`


Integrate the rational function:

`(2x)/(x^2 + 3x + 2)`


Integrate the rational function:

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


Integrate the rational function:

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


Integrate the rational function:

`(3x + 5)/(x^3 - x^2 - x + 1)`


Integrate the rational function:

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


Integrate the rational function:

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


Integrate the rational function:

`1/(x^4 - 1)`


Integrate the rational function:

`((x^2 +1)(x^2 + 2))/((x^2 + 3)(x^2+ 4))`


`int (dx)/(x(x^2 + 1))` equals:


Integrate the following w.r.t. x : `(2x)/((2 + x^2)(3 + x^2)`


Integrate the following w.r.t. x: `(1)/(sinx + sin2x)`


Integrate the following w.r.t. x : `(1)/(sin2x + cosx)`


Integrate the following with respect to the respective variable : `(6x + 5)^(3/2)`


Integrate the following w.r.t. x: `(2x^2 - 1)/(x^4 + 9x^2 + 20)`


Integrate the following with respect to the respective variable : `cot^-1 ((1 + sinx)/cosx)`


Integrate the following w.r.t.x : `x^2/sqrt(1 - x^6)`


Integrate the following w.r.t.x : `(1)/((1 - cos4x)(3 - cot2x)`


Integrate the following w.r.t.x : `(1)/(2cosx + 3sinx)`


Integrate the following w.r.t.x : `(1)/(sinx + sin2x)`


Evaluate:

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


Evaluate: `int "3x - 2"/(("x + 1")^2("x + 3"))` dx


For `int ("x - 1")/("x + 1")^3  "e"^"x" "dx" = "e"^"x"` f(x) + c, f(x) = (x + 1)2.


`int (2x - 7)/sqrt(4x- 1) dx`


`int "e"^(3logx) (x^4 + 1)^(-1) "d"x`


`int (6x^3 + 5x^2 - 7)/(3x^2 - 2x - 1)  "d"x`


`int x^3tan^(-1)x  "d"x`


`int ("d"x)/(x^3 - 1)`


`int (sin2x)/(3sin^4x - 4sin^2x + 1)  "d"x`


`int  ((2logx + 3))/(x(3logx + 2)[(logx)^2 + 1])  "d"x`


Choose the correct alternative:

`int (x + 2)/(2x^2 + 6x + 5) "d"x = "p"int (4x + 6)/(2x^2 + 6x + 5) "d"x + 1/2 int 1/(2x^2 + 6x + 5)"d"x`, then p = ?


Evaluate `int (2"e"^x + 5)/(2"e"^x + 1)  "d"x`


Evaluate `int x log x  "d"x`


Evaluate `int x^2"e"^(4x)  "d"x`


`int 1/(4x^2 - 20x + 17)  "d"x`


Evaluate the following:

`int (2x - 1)/((x - 1)(x + 2)(x - 3)) "d"x`


Evaluate the following:

`int sqrt(tanx)  "d"x`  (Hint: Put tanx = t2)


If `int 1/((x^2 + 4)(x^2 + 9))dx = A tan^-1  x/2 + B tan^-1(x/3) + C`, then A – B = ______.


If `intsqrt((x - 5)/(x - 7))dx = Asqrt(x^2 - 12x + 35) + log|x| - 6 + sqrt(x^2 - 12x + 35) + C|`, then A = ______.


Find: `int x^4/((x - 1)(x^2 + 1))dx`.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×