помогите сроооочно найти интеграл!!!! C(x)=корень из x+1 поделить на x, C'(3)

sqrt(x+1) / x dx
делаем замену 1+x = sqrt(t) ==>dx = 1/(2sqrt(t)) dt
x=sqrt(t) -1

==>1/2 t^(1/4) / (sqrt(t) -1) * t^(-1/2) dt = 1/2 1 / t^(1/4) (t^(1/2) -1) dt =
= [ t^(1/4) = y ==> t= y^4 ==>dt = 4y^3 dy ] = 1/2 *1/ (y *(y^2 -1))* 4y^3 dy =
= 2 * y^2 / (y^2 -1) dy = 2 (1 +1/(y^2 -1)) dy = 2dy +1/(y-1) dy -1/(y+1) dy

интегрируем

2y +ln(y-1) -ln(y+1) = 2*t^(1/4) +ln(t^(1/4) -1) - ln(t^(1/4) +1) = 2*sqrt(1+x) + ln(sqrt(1+x) -1) -ln(sqrt(1+x) +1)