English Deutsch Français Italiano Español Português 繁體中文 Bahasa Indonesia Tiếng Việt ภาษาไทย
All categories

This problem looks like one for u substitution but I have tried to use that and cant figure out a way!

2007-05-08 08:13:28 · 3 answers · asked by Dolphin Man 2 in Science & Mathematics Mathematics

3 answers

int [(1/x+1)*(1/sqrt(x)) dx]
set
u = sqrt x
du = dx/(2*sqrtx)
2 * du = dx/sqrtx
But:
u^2 = x
u^2 + 1 = x + 1
so we get:
int [2 du/(u^2+1)] =
= 2 int [1/(u^2+1) du]
= 2 * tan u + c
= 2 * tan (sqrtx) + c

2007-05-08 08:36:55 · answer #1 · answered by Baselek 2 · 0 0

let u = sqrt(x)
du = (1/2) x^(-1/2)dx

the integral becomes
(u^-2 + 1) 2 du

2007-05-08 15:21:31 · answer #2 · answered by doctor risk 3 · 0 0

2 arctg(sqrt(x)) + constant

2007-05-08 15:17:58 · answer #3 · answered by gjmb1960 7 · 0 0

fedest.com, questions and answers