Integrate? S10/√(2+√x)dx

1 Answer
Mar 2, 2018

I=40/3(2+sqrt(x))^(3/2)-80sqrt(2+sqrt(x))+CI=403(2+x)32802+x+C

Explanation:

I assume you mean, and the S is meant as an integral sign :)

I=int10/(sqrt(2+sqrt(x)))dxI=102+xdx

Make a substitution u=2+sqrt(x)=>(du)/dx=1/(2sqrt(x))u=2+xdudx=12x

I=int10/(sqrt(u))2sqrt(x)dxI=10u2xdx

But u=2+sqrt(x)=>sqrt(x)=u-2u=2+xx=u2

I=int10/(sqrt(u))2(u-2)dx=20intsqrt(u)-2/sqrt(u)duI=10u2(u2)dx=20u2udu

Integrate

I=20(2/3u^(3/2)-4sqrt(u))+CI=20(23u324u)+C

Substitute back u=2+sqrt(x)u=2+x

I=20(2/3(2+sqrt(x))^(3/2)-4sqrt(2+sqrt(x)))+CI=20(23(2+x)3242+x)+C

I=40/3(2+sqrt(x))^(3/2)-80sqrt(2+sqrt(x))+CI=403(2+x)32802+x+C