Given,
`int sqrt(1-x)/sqrt(x) dx`
let us consider `u= sqrt(x)` ,
we can write it as `u^2 = x`
Differentiating on both sides we get
=> `(2u)du = dx`
Now let us solve the integral ,
`int sqrt(1-x)/sqrt(x) dx`
=`int sqrt(1-u^2)/(u) ((2u)du)` [as `x= u^2` ]
=`int 2*sqrt(1-u^2) du`
= `2int sqrt(1-u^2) du---(1)`
This can be solved by using the Trigonometric substitutions (Trig substitutions)
For `sqrt(a-bx^2)` we have to take `x=` `sqrt(a/b) sin(v)`
so here , For
`2 int sqrt(1-u^2) du` let us take `u = sqrt(1/1) sin(v) = sin(v)`
as `u= sin(v)` `=>` `du = cos(v) dv`
now substituting in (1) we get
`2int sqrt(1-u^2) du`
= `2int sqrt(1-(sin(v))^2) (cos(v) dv)`
= `2int sqrt((cos(v))^2) (cos(v) dv)`
= `2 int cos(v) cos(v) dv`
= `2 int cos^2(v) dv`
=`2 int (1+cos(2v))/2 dv`
= `(2/2) int (1+cos(2v)) dv`
= `int (1+cos(2v))dv`
=` [v+(1/2)(sin(2v))]+c`
but ,
`u = sin(v)`
=> `v= sin^(-1) u` and `u= sqrt(x)`
so,
`v= sin^(-1) (sqrt(x))`
now,
`v+1/2sin(2v)+c`
=`sin^(-1) (sqrt(x))+1/2sin(2sin^(-1) (sqrt(x)))+c`
so,
`int sqrt(1-x)/sqrt(x) dx`
=
=`sin^(-1) (sqrt(x))+1/2sin(2sin^(-1) (sqrt(x)))+c`
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