हिंदी

∫sinxsin3x dx - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

`int (sinx)/(sin3x)  "d"x`

योग

उत्तर

Let I = `int (sinx)/(sin3x)  "d"x`

= `int sin x/(3sin x - 4 sin^3x)* "d"x`

= `int sinx/(sinx(3 - 4sin^2x))* "d"x`

= `int 1/(3 - 4sin^2x)  "d"x`

Dividing numerator and denominator by cos2x, we get

I = `int (sec^2x)/(3sec^2x - 4tan^2x) * "d"x`

= `int (sec^2x)/(3(1 + tan^2x) - 4tan^2x)* "d"x`

= `int (sec^2x)/(3 - tan^2x)  "d"x`

Put tan x = t

∴ sec2x dx = dt

∴ I = `int "dt"/(3 - "t"^2)`

= `int 1/((sqrt(3))^2 - "t"^2)  "dt"`

=`1/(2sqrt(3)) log|(sqrt(3) + "t")/(sqrt(3) - "t")| + "c"`

∴ I = `1/(2sqrt(3)) log|(sqrt(3) + tanx)/(sqrt(3) - tanx)| + "c'` 

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

वीडियो ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्न

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


Evaluate:

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


Integrate the rational function:

`1/(x^2 - 9)`


Integrate the rational function:

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


Integrate the rational function:

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


Integrate the rational function:

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


Integrate the rational function:

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


Integrate the rational function:

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


Integrate the rational function:

`(5x)/((x + 1)(x^2 - 4))`


Integrate the rational function:

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


Integrate the rational function:

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


Integrate the rational function:

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


Integrate the rational function:

`1/(x(x^n + 1))` [Hint: multiply numerator and denominator by xn − 1 and put xn = t]


Integrate the rational function:

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


Integrate the rational function:

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


Evaluate : `∫(x+1)/((x+2)(x+3))dx`


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


Find : 

`∫ sin(x-a)/sin(x+a)dx`


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


Integrate the following w.r.t. x:

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


Integrate the following w.r.t. x : `(12x^2 - 2x - 9)/((4x^2 - 1)(x + 3)`


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


Integrate the following w.r.t. x : `(5x^2 + 20x + 6)/(x^3 + 2x ^2 + x)`


Integrate the following w.r.t. x : `(1)/(x(1 + 4x^3 + 3x^6)`


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


Integrate the following w.r.t. x : `((3sin - 2)*cosx)/(5 - 4sin x - cos^2x)`


Integrate the following w.r.t. x : `(1)/(2sinx + sin2x)`


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


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


Integrate the following w.r.t. x : `(5*e^x)/((e^x + 1)(e^(2x) + 9)`


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


Integrate the following with respect to the respective variable : `(cos 7x - cos8x)/(1 + 2 cos 5x)`


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


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


Integrate the following w.r.t.x :  `sec^2x sqrt(7 + 2 tan x - tan^2 x)`


Integrate the following w.r.t.x : `(x + 5)/(x^3 + 3x^2 - x - 3)`


Integrate the following w.r.t.x : `sqrt(tanx)/(sinx*cosx)`


Evaluate: `int (2"x" + 1)/("x"("x - 1")("x - 4"))` dx


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


Evaluate: `int 1/("x"("x"^5 + 1))` dx


`int "dx"/(("x" - 8)("x" + 7))`=


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


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


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


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


`int sqrt((9 + x)/(9 - x))  "d"x`


`int sec^3x  "d"x`


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


`int (x + sinx)/(1 - cosx)  "d"x`


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


`int 1/(sinx(3 + 2cosx))  "d"x`


Choose the correct alternative:

`int sqrt(1 + x)  "d"x` =


State whether the following statement is True or False:

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


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


Evaluate `int x log x  "d"x`


Verify the following using the concept of integration as an antiderivative

`int (x^3"d"x)/(x + 1) = x - x^2/2 + x^3/3 - log|x + 1| + "C"`


Evaluate the following:

`int x^2/(1 - x^4) "d"x` put x2 = t


Evaluate the following:

`int_"0"^pi  (x"d"x)/(1 + sin x)`


Evaluate the following:

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


Evaluate the following:

`int "e"^(-3x) cos^3x  "d"x`


If `int "dx"/((x + 2)(x^2 + 1)) = "a"log|1 + x^2| + "b" tan^-1x + 1/5 log|x + 2| + "C"`, then ______.


The numerator of a fraction is 4 less than its denominator. If the numerator is decreased by 2 and the denominator is increased by 1, the denominator becomes eight times the numerator. Find the fraction.


Evaluate: `int (dx)/(2 + cos x - sin x)`


Let g : (0, ∞) `rightarrow` R be a differentiable function such that `int((x(cosx - sinx))/(e^x + 1) + (g(x)(e^x + 1 - xe^x))/(e^x + 1)^2)dx = (xg(x))/(e^x + 1) + c`, for all x > 0, where c is an arbitrary constant. Then ______.


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


Evaluate: 

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


Evaluate:

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


Evaluate.

`int (5x^2 - 6x + 3) / (2x -3) dx`


Evaluate:

`int (x + 7)/(x^2 + 4x + 7)dx`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×