English

Evaluate the following. ∫3ex+42ex-8dx - Mathematics and Statistics

Advertisements
Advertisements

Question

Evaluate the following.

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

Sum
Advertisements

Solution

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

Put, Numerator = A(Denominator) + B[`d/dx`(Denominator)]

Let 3ex + 4 = A(2ex - 8) + B `"d"/"dx"`(2ex - 8)

= 2 Aex - 8A + B(2ex )

∴ 3ex + 4 = (2A + 2B)ex - 8A

Comparing the coefficients of ex and constant term on both sides, we get

2A + 2B = 3 and - 8A = 4

Solving these equations, we get

A = `- 1/2` and B = 2

∴ I = `int (- 1/2 (2"e"^"x" - 8) + 2(2"e"^"x"))/(2"e"^"x" - 8)`dx

`= - 1/2 int "dx" + 2 int ("2e"^"x")/(2"e"^"x" - 8)` dx

∴ I = `- 1/2"x" + 2log |2"e"^"x" - 8|` + c     ...`[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 5.3 [Page 123]

RELATED QUESTIONS

Find : `int((2x-5)e^(2x))/(2x-3)^3dx`


Integrate the functions:

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


Integrate the functions:

`sqrt(sin 2x) cos 2x`


Integrate the functions:

`cos x /(sqrt(1+sinx))`


\[\int\sqrt{9 - x^2}\text{ dx}\]

Write a value of

\[\int e^{2 x^2 + \ln x} \text{ dx}\]

Write a value of\[\int\left( e^{x \log_e \text{  a}} + e^{a \log_e x} \right) dx\] .


Write a value of\[\int e^{ax} \left\{ a f\left( x \right) + f'\left( x \right) \right\} dx\] .


If `f'(x) = x - (3)/x^3, f(1) = (11)/(2)`, find f(x)


Integrate the following functions w.r.t. x:

`x^5sqrt(a^2 + x^2)`


Integrate the following functions w.r.t. x : tan5x


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


If f '(x) = `"x"^2/2 - "kx" + 1`, f(0) = 2 and f(3) = 5, find f(x).


Evaluate the following.

`int 1/("a"^2 - "b"^2 "x"^2)` dx


Evaluate the following.

`int 1/(sqrt(3"x"^2 - 5))` dx


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


State whether the following statement is True or False.

If `int x  "e"^(2x)` dx is equal to `"e"^(2x)` f(x) + c, where c is constant of integration, then f(x) is `(2x - 1)/2`.


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


Evaluate: `int log ("x"^2 + "x")` dx


State whether the following statement is True or False:

`int"e"^(4x - 7)  "d"x = ("e"^(4x - 7))/(-7) + "c"`


`int x^3"e"^(x^2) "d"x`


If `tan^-1x = 2tan^-1((1 - x)/(1 + x))`, then the value of x is ______ 


If `int(cosx - sinx)/sqrt(8 - sin2x)dx = asin^-1((sinx + cosx)/b) + c`. where c is a constant of integration, then the ordered pair (a, b) is equal to ______.


Find `int (x + 2)/sqrt(x^2 - 4x - 5) dx`.


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


Evaluate.

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


Evaluate:

`int sin^3x cos^3x  dx`


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


Evaluate the following.

`int1/(x^2+4x-5)dx`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×