English

Evaluate the integral by using substitution. ∫02xx+2 (Put x + 2 = t2)

Advertisements
Advertisements

Question

Evaluate the integral by using substitution.

`int_0^2 xsqrt(x+2)`  (Put x + 2 = `t^2`)

Sum
Advertisements

Solution

Let `I = int_0^2 x sqrt (x + 2) dx`

Put x + 2 = t

⇒ dx = dt

When x = 0, t = 2 and when x = 2, t = 4

∴ `I = int_2^4 (t - 2) sqrtt  dt `

`= int_2^4 (t^(3/2) - 2t^(1/2)) dt`

`= [2/5 t^(5/2) - 2 xx 2/3 t^(3/2)]_2^4`

`= [2/5 (4)^(5/2) - 4/3 t^(3/2)]_2^4`

`= [2/5 (4)^(5/2) - 4/3 (4)^(3/2)] - [2/5 (2)^(5/2) = 4/3 (2)^(3/2)]`

`= 2/5 (2)^5 - 4/3 (2)^3 - 2/5 xx 4sqrt2 + 4/3 xx 2sqrt2`

`= 2/5 xx 32 - 4/3 xx 8 - 8/5 sqrt2 + 8/3 sqrt2`

`= 64/5 - 32/3 - (8/5 sqrt2 - 8/3 sqrt2)`

`= (192 - 160)/15 - ((24sqrt2 - 40sqrt2))/15`

`= 32/15 + (16sqrt2)/15`

`= 16/15 (2+sqrt2)`

or `(16sqrt2)/15 (sqrt2+1)`

shaalaa.com
  Is there an error in this question or solution?
Chapter 7: Integrals - Exercise 7.10 [Page 340]

APPEARS IN

NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 7 Integrals
Exercise 7.10 | Q 4 | Page 340

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

Evaluate :`int_0^(pi/2)1/(1+cosx)dx`

 


Evaluate : `int1/(3+5cosx)dx`


 

find `∫_2^4 x/(x^2 + 1)dx`

 

Evaluate: `intsinsqrtx/sqrtxdx`

 


Evaluate the integral by using substitution.

`int_0^1 x/(x^2 +1)`dx


Evaluate `int_0^(pi/4) (sinx + cosx)/(16 + 9sin2x) dx`


Evaluate of the following integral:

(i)  \[\int x^4 dx\]

 


Evaluate of the following integral: 

\[\int x^\frac{5}{4} dx\]

Evaluate of the following integral:

\[\int \log_x \text{x  dx}\] 

Evaluate: 

\[\int\sqrt{\frac{1 + \cos 2x}{2}}dx\]

Evaluate: 

\[\int\frac{1}{a^x b^x}dx\]

Evaluate:

\[\int\frac{e\log \sqrt{x}}{x}dx\]

Evaluate the following integral:

\[\int\limits_{- 2}^2 \left| x + 1 \right| dx\]

 


Evaluate the following integral:

\[\int\limits_1^2 \left| x - 3 \right| dx\]

Evaluate the following integral:

\[\int\limits_{- \pi/4}^{\pi/4} \left| \sin x \right| dx\]

Evaluate the following integral:

\[\int\limits_0^4 \left| x - 1 \right| dx\]

Evaluate the following integral:

\[\int\limits_{- 5}^0 f\left( x \right) dx, where\ f\left( x \right) = \left| x \right| + \left| x + 2 \right| + \left| x + 5 \right|\]

 


Evaluate each of the following integral:

\[\int_0^{2\pi} \frac{e^\ sin x}{e^\ sin x + e^{- \ sin x}}dx\]

 


Evaluate each of the following integral:

\[\int_{- \frac{\pi}{2}}^\frac{\pi}{2} \frac{\cos^2 x}{1 + e^x}dx\]

Evaluate 

\[\int\limits_0^\pi \frac{x}{1 + \sin \alpha \sin x}dx\]


Evaluate the following integral:

\[\int_0^\frac{\pi}{2} \frac{a\sin x + b\sin x}{\sin x + \cos x}dx\]

 


Evaluate : 

\[\int\limits_0^{3/2} \left| x \sin \pi x \right|dx\]

Evaluate : \[\int\limits_{- 2}^1 \left| x^3 - x \right|dx\] .


Find : \[\int\frac{x \sin^{- 1} x}{\sqrt{1 - x^2}}dx\] .


Evaluate: `int_-π^π (1 - "x"^2) sin "x" cos^2 "x"  d"x"`.


Evaluate: `int_1^5{|"x"-1|+|"x"-2|+|"x"-3|}d"x"`.


`int_0^3 1/sqrt(3x - x^2)"d"x` = ______.


`int_0^(pi4) sec^4x  "d"x` = ______.


`int_0^1 sin^-1 ((2x)/(1 + x^2))"d"x` = ______.


Find: `int (dx)/sqrt(3 - 2x - x^2)`


The value of `int_0^1 (x^4(1 - x)^4)/(1 + x^2) dx` is


If `int x^5 cos (x^6)dx = k sin (x^6) + C`, find the value of k.


If the substitution is \[t=g(x)\], what differential relation is used in Method 2: Changing the Limits?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×