English

Evaluate the following. ∫1xlogxdx

Advertisements
Advertisements

Question

Evaluate the following.

`int 1/("x" log "x")`dx

Sum
Advertisements

Solution

Let I = `int 1/("x" log "x")`dx

Put log x = t

∴ `1/"x" "dx" = "dt'`

∴ I = `int 1/"t"` dt = log |t| + c

∴ I = log |log x| + c

Alternate Method:

Let I = `int 1/("x" * log "x")`dx

`= int (1//"x"  "dx")/(log "x")`

∴ I = log |log x| + c      .....`[because int ("f" '("x"))/("f"("x")) "dx" = log |"f"("x")| + "c"]`

shaalaa.com
  Is there an error in this question or solution?
Chapter 5: Integration - EXERCISE 5.2 [Page 123]

RELATED QUESTIONS

Integrate the functions:

`xsqrt(1+ 2x^2)`


Integrate the functions:

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


Integrate the functions:

`sin x/(1+ cos x)`


Evaluate : `∫1/(3+2sinx+cosx)dx`


Solve:

dy/dx = cos(x + y)


Evaluate: `int (2y^2)/(y^2 + 4)dx`


Write a value of\[\int\text{ tan x }\sec^3 x\ dx\]


Write a value of\[\int \log_e x\ dx\].

 


Write a value of\[\int\sqrt{x^2 - 9} \text{ dx}\]


Evaluate the following integrals : `int cos^2x.dx`


Integrate the following functions w.r.t. x : `(1 + x)/(x.sin (x + log x)`


Integrate the following functions w.r.t. x : `(1)/(4x + 5x^-11)`


Integrate the following functions w.r.t. x : `cosx/sin(x - a)`


Evaluate the following : `int sqrt((9 + x)/(9 - x)).dx`


Evaluate the following : `int (1)/(1 + x - x^2).dx`


Evaluate the following : `int (1)/(5 - 4x - 3x^2).dx`


Integrate the following functions w.r.t. x : `int (1)/(4 - 5cosx).dx`


Choose the correct options from the given alternatives :

`int f x^x (1 + log x)*dx`


Evaluate the following.

`int 1/(sqrt"x" + "x")` dx


Evaluate the following.

`int (3"e"^"x" + 4)/(2"e"^"x" - 8)`dx


Evaluate the following.

`int 1/(4x^2 - 20x + 17)` dx


`int (x^2 + x - 6)/((x - 2)(x - 1))dx = x` + ______ + c


`int e^x/x [x (log x)^2 + 2 log x]` dx = ______________


`int (log x)/(log ex)^2` dx = _________


General solution of `(x + y)^2 ("d"y)/("d"x) = "a"^2, "a" ≠ 0` is ______. (c is arbitrary constant)


If `int sinx/(sin^3x + cos^3x)dx = α log_e |1 + tan x| + β log_e |1 - tan x + tan^2x| + γ tan^-1 ((2tanx - 1)/sqrt(3)) + C`, when C is constant of integration, then the value of 18(α + β + γ2) is ______.


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


If f ′(x) = 4x3 − 3x2 + 2x + k, f(0) = 1 and f(1) = 4, find f(x)


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


In \[\int\sin^3x\cos^2x\,dx\], which rewriting prepares the integrand for the substitution \[t=\cos x\]?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×