मराठी

Evaluate: π∫0πx1+sinxdx.

Advertisements
Advertisements

प्रश्न

Evaluate: `int_0^π x/(1 + sinx)dx`.

बेरीज
Advertisements

उत्तर

`int_0^π x/(1 + sinx)dx`

Let I = `int_0^π x/(1 + sinx)dx`  ...(i)

On using property

`int_0^a f(x)dx = int_0^a f(a - x)dx`

∴ I = `int_0^π (π - x)/(1 + sin(π - x))dx`

I = `int_0^π (π - x)/(1 + sinx)dx`  ...(ii)

Adding equations (i) and (ii), we get

2I = `int_0^π π/(1 + sinx)dx`

= `πint_0^π 1/(1 + sinx) xx (1 - sinx)/(1 - sinx)dx`  ...[Multiplying and dividing by (1 – sin x)]

= `πint_0^π (1 - sinx)/(1 - sin^2x)dx = πint_0^π (1 - sinx)/(cos^2x)dx`

= `π[int_0^π 1/(cos^2x)dx - int_0^π sinx/(cos^2x)dx]`

= `π[int_0^π sec^2x  dx - int_0^π secx tanx  dx]`

= `π[[tanx]_0^π - [secx]_0^π]`

= π[0 – (– 1 – 1)]

= 2π

∴ I = `(2π)/2` = π.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
2022-2023 (March) Delhi Set 2

संबंधित प्रश्‍न

If `int_0^alpha3x^2dx=8` then the value of α is :

(a) 0

(b) -2

(c) 2 

(d) ±2


 
 

Evaluate `int_(-2)^2x^2/(1+5^x)dx`

 
 

By using the properties of the definite integral, evaluate the integral:

`int_(-5)^5 | x + 2| dx`


By using the properties of the definite integral, evaluate the integral:

`int_0^(2x) cos^5 xdx`


Evaluate : `int 1/("x" [("log x")^2 + 4])  "dx"`


The total revenue R = 720 - 3x2 where x is number of items sold. Find x for which total  revenue R is increasing.


Using properties of definite integrals, evaluate 

`int_0^(π/2)  sqrt(sin x )/ (sqrtsin x + sqrtcos x)dx`


State whether the following statement is True or False:

`int_(-5)^5 x/(x^2 + 7)  "d"x` = 10


Evaluate `int_1^3 x^2*log x  "d"x`


By completing the following activity, Evaluate `int_2^5 (sqrt(x))/(sqrt(x) + sqrt(7 - x))  "d"x`.

Solution: Let I = `int_2^5 (sqrt(x))/(sqrt(x) + sqrt(7 - x))  "d"x`     ......(i)

Using the property, `int_"a"^"b" "f"(x) "d"x = int_"a"^"b" "f"("a" + "b" - x)  "d"x`, we get

I = `int_2^5 ("(  )")/(sqrt(7 - x) + "(  )")  "d"x`   ......(ii)

Adding equations (i) and (ii), we get

2I = `int_2^5 (sqrt(x))/(sqrt(x) - sqrt(7 - x))  "d"x + (   )  "d"x`

2I = `int_2^5 (("(    )" + "(     )")/("(    )" + "(     )"))  "d"x`

2I = `square`

∴ I =  `square`


`int_0^{pi/2}((3sqrtsecx)/(3sqrtsecx + 3sqrt(cosecx)))dx` = ______ 


`int_0^9 1/(1 + sqrtx)` dx = ______ 


Evaluate `int_0^(pi/2) (tan^7x)/(cot^7x + tan^7x) "d"x`


Evaluate `int_(-1)^2 "f"(x)  "d"x`, where f(x) = |x + 1| + |x| + |x – 1|


Evaluate: `int_(pi/6)^(pi/3) (dx)/(1 + sqrt(tanx)`


Evaluate: `int_0^(π/2) 1/(1 + (tanx)^(2/3)) dx`


If `int_a^b x^3 dx` = 0, then `(x^4/square)_a^b` = 0

⇒ `1/4 (square - square)` = 0

⇒ b4 – `square` = 0

⇒ (b2 – a2)(`square` + `square`) = 0

⇒ b2 – `square` = 0 as a2 + b2 ≠ 0

⇒ b = ± `square`


`int_a^b f(x)dx` = ______.


`int_a^b f(x)dx = int_a^b f(x - a - b)dx`.


`int_0^5 cos(π(x - [x/2]))dx` where [t] denotes greatest integer less than or equal to t, is equal to ______.


If f(x) = `(2 - xcosx)/(2 + xcosx)` and g(x) = logex, (x > 0) then the value of the integral `int_((-π)/4)^(π/4) "g"("f"(x))"d"x` is ______.


`int_0^1|3x - 1|dx` equals ______.


If `β + 2int_0^1x^2e^(-x^2)dx = int_0^1e^(-x^2)dx`, then the value of β is ______.


The value of the integral `int_0^sqrt(2)([sqrt(2 - x^2)] + 2x)dx` (where [.] denotes greatest integer function) is ______.


Evaluate the following limit :

`lim_("x"->3)[sqrt("x"+6)/"x"]`


`int_0^(2a)f(x)/(f(x)+f(2a-x))  dx` = ______


Evaluate the following integral:

`int_0^1 x(1-x)^5 dx`


Evaluate the following integral:

`int_-9^9x^3/(4-x^2)dx`


Evaluate:

`int_0^6 |x + 3|dx`


Evaluate the following definite intergral:

`int_1^3logx  dx`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×