English

Evaluate : ∫ π 2 0 Sin X . Cos X 1 + Sin 4 X .Dx - Mathematics and Statistics

Advertisements
Advertisements

Question

Evaluate : `∫_0^(pi/2) (sinx.cosx)/(1 + sin^4x)`.dx

Sum

Solution

Let I = `∫_0^(pi/2) (sinx.cosx)/(1 + sin^4x)`.dx

Put `sin^2x  = t`

2sinx cosx dx = dt

`sinx cosx  dx = dt/2`

When x = 0 , t = 0

`x = pi/2` , t = 1

∴ I = `∫_0^1 (dt/2)/(1 + t^2)`

= `∫_0^1 1/2[dt/(1 + t^2)]`

= `[1/2 (tan^-1 t)]_0^1`

= `1/2[tan^-1 1 - tan^-1 0]`

= `1/2[pi/4 - 0]`

`"I" = pi/8`

shaalaa.com
  Is there an error in this question or solution?
2016-2017 (March)

APPEARS IN

Video TutorialsVIEW ALL [1]

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×