हिंदी

Evaluate the following: d∫tanx dx (Hint: Put tanx = t2) - Mathematics

Advertisements
Advertisements

प्रश्न

Evaluate the following:

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

योग

उत्तर

Let I = `int sqrt(tanx)  "d"x` 

Put tan x = t2

⇒ sec2x dx = 2t dt

∴ I = `int "t" * (2"t")/(sec^2x) "dt"`

= `2 int "t"^2/(1 + "t"^4) "dt"`

= `int (("t"^2 + 1) + ("t"^2 - 1))/((1 + "t"^4)) "dt"`

= `int ("t"^2 + 1)/(1 + "t"^4) "dt" + int ("t"^2 - 1)/(1 + "t"^4) "dt"`

= `int (1 + 1/"t"^2)/("t"^2 + 1/"t"^2) "dt" + int (1 - 1/"t"^2)/("t"^2 + 1/"t"^2) "dt"`

= `int (1 + 1/"t"^2)/(("t" - 1/"t")^2 + 2)"dt" + int (1 - 1/"t"^2)/(("t" + 1/"t")^2 - 2)"dt"`

Put u = `"t" - 1/"t"`

⇒ du = `(1 + 1/"t"^2)"dt"` in first integral

And put v = `"t" + 1/"t"`

⇒ dv = `(1 - 1/"t"^2)"dt"` in second integral

∴ I = `int "du"/("u"^2 + (sqrt(2)^2)) + int "dv"/("v"^2 - (sqrt(2)^2))`

= `1/sqrt(2) tan^-1  "u"/sqrt(2) + 1/(2sqrt(2)) log|("v" - sqrt(2))/("v" + sqrt(2))| + "C"`

= `1/sqrt(2) tan^-1  ("t" - 1/"t")/sqrt(2) + 1/(2sqrt(2)) log |("t" + 1/"t" - sqrt(2))/("t" + 1/"t" + sqrt(2))| + "C"`

= `1/sqrt(2) tan^-1  ("t"^2 - 1)/(sqrt(2)"t") + 1/(2sqrt(2)) log |("t"^2 + 1 - sqrt(2)"t")/("t"^2 + 1 + sqrt(2)"t")| + "C"`

= `1/sqrt(2) tan^-1  ((tanx - 1)/sqrt(2tan x)) + 1/(2sqrt(2)) log |(tan x - sqrt(2 tanx) + 1)/(tan x + sqrt(2 tan x) + 1)| + "C"`

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 7: Integrals - Exercise [पृष्ठ १६६]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
अध्याय 7 Integrals
Exercise | Q 43 | पृष्ठ १६६

संबंधित प्रश्न

Integrate the rational function:

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


Integrate the rational function:

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


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


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


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 : `(5*e^x)/((e^x + 1)(e^(2x) + 9)`


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


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


`int 1/(4x^2 - 20x + 17)  "d"x`


`int sec^3x  "d"x`


`int "e"^(sin^(-1_x))[(x + sqrt(1 - x^2))/sqrt(1 - x^2)] "d"x`


`int ("d"x)/(2 + 3tanx)`


`int (x + sinx)/(1 - cosx)  "d"x`


`int (5(x^6 + 1))/(x^2 + 1) "d"x` = x5 – ______ x3 + 5x + c


Evaluate the following:

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


Evaluate the following:

`int (x^2 "d"x)/((x^2 + "a"^2)(x^2 + "b"^2))`


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 ______.


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


If `int dx/sqrt(16 - 9x^2)` = A sin–1 (Bx) + C then A + B = ______.


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


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×