हिंदी

∫3x+42x2+2x+1 dx

Advertisements
Advertisements

प्रश्न

`int (3x + 4)/sqrt(2x^2 + 2x + 1)  "d"x`

योग
Advertisements

उत्तर

Let I = `int (3x + 4)/sqrt(2x^2 + 2x + 1)  "d"x`

Let 3x + 4 = `"A" "d"/("d"x)(2x^2 + 2x + 1) + "B"`

 ∴ 3x + 4 = A(4x + 2) + B

∴ 3x + 4 = 4Ax + 2A + B

By equating the coefficients on both sides, we get

4A = 3 and 2A + B = 4

∴ A = `3/4` and `2(3/4) + "B"` = 4

∴ B = `5/2`

∴ 3x + 4 = `3/4(4x + 2) + 5/2`

∴ I = `int (3/4(4x + 2) + 5/2)/sqrt(2x^2 + 2x + 1) "d"x`

= `3/4 int (4x + 2)/sqrt(2x^2 + 2x + 1)  "d"x + 5/2 int 1/sqrt(2x^2 + 2x + 1)  "d"x`

= I1 + I2             ........(i)

I1 = `3/4 int (4x + 2)/sqrt(2x^2 + 2x + 1)  "d"x`

 Put 2x2 + 2x + 1 = t

∴ (4x + 2) dx = dt

∴ I1 = `3/4 int "dt"/sqrt("t")`

= `3/4 int "t"^(1/2)  "dt"`

= `3/4("t"^(1/2)/(1/2)) + "c"_1`

= `3/2 sqrt("t") + "c"_1`

∴ I1 = `3/2 sqrt(2x^2 + 2x + 1) + "c"_1`    .........(ii)

I2 = `5/2 int 1/sqrt(2x^2 + 2x + 1)  "d"x`

= `5/2 int 1/sqrt(2(x^2 + x + 1/2))  "d"x`

`(1/2  "coefficient of"  x)^2 = (1/2 xx 1)^2`

= `1/4`

∴ I2 = `5/(2sqrt(2)) int 1/sqrt(x^2 + x + 1/4 - 1/4 + 1/2)  "d"x`

= `5/(2sqrt(2)) int 1/sqrt((x + 1/2)^2 - (1/2)^2)  "d"x`

= `5/(2sqrt(2)) log|x + 1/2 + sqrt((x + 1/2)^2 - (1/2)^2)| + "c"_2`

∴ I2 = `5/(2sqrt(2)) log|x + 1/2 + sqrt(x^2 + x + 1/2)| + "c"_2`    ........(iii)

From (i), (ii) and (iii), we get

I = `3/2 sqrt(2x^2 + 2x + 1) + 5/(2sqrt(2)) log|x + 1/2 + sqrt(x^2 + x + 1/2)| + "c"`,

where c = c1 + c2    

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

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


Find: `I=intdx/(sinx+sin2x)`


Integrate the rational function:

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


Integrate the rational function:

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


Integrate the rational function:

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


Integrate the rational function:

`1/(e^x -1)`[Hint: Put ex = t]


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


Find `int (2cos x)/((1-sinx)(1+sin^2 x)) dx`


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


Integrate the following w.r.t. x : `(12x + 3)/(6x^2 + 13x - 63)`


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


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)/(2cosx + 3sinx)`


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


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


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


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


Evaluate: `int (2"x"^3 - 3"x"^2 - 9"x" + 1)/("2x"^2 - "x" - 10)` dx


`int x^2sqrt("a"^2 - x^6)  "d"x`


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


`int sqrt((9 + x)/(9 - x))  "d"x`


`int (sinx)/(sin3x)  "d"x`


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


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


`int x^3tan^(-1)x  "d"x`


`int (x + sinx)/(1 - cosx)  "d"x`


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


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


Choose the correct alternative:

`int sqrt(1 + x)  "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 = ?


If f'(x) = `1/x + x` and f(1) = `5/2`, then f(x) = log x + `x^2/2` + ______ + c


If `int(sin2x)/(sin5x  sin3x)dx = 1/3log|sin 3x| - 1/5log|f(x)| + c`, then f(x) = ______


Evaluate the following:

`int "e"^(-3x) cos^3x  "d"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 ______.


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`.


Evaluate:

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


Evaluate.

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


Integration by partial fractions is a method used to integrate which functions?


A proper rational function can be expressed as a sum of simpler rational functions called what?


Which partial form corresponds to \[\frac{\mathrm{p}x^{2}+\mathrm{q}x+\mathrm{r}}{(x-\mathrm{a})(x-\mathrm{b})(x-\mathrm{c})}\]?


Which partial form is appropriate for \[\frac{\mathrm{p}x^{2}+\mathrm{q}x+\mathrm{r}}{(x-\mathrm{a})^{2}(x-\mathrm{b})}\]?


What is the result of dividing \[x^{2}+1\] by \[x^{2}-5x+6\]?


Which pair of equations is obtained by equating coefficients in \[5x-5=\mathrm{A}(x-3)+\mathrm{B}(x-2)\]?


What are the values of \[\mathrm{A}\] and \[\mathrm{B}\] in \[\frac{5x-5}{(x-2)(x-3)}=\frac{\mathrm{A}}{x-2}+\frac{\mathrm{B}}{x-3}\]?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×