Math Is Fun Forum

  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#1 2005-09-12 02:33:51

Archon
Member
Registered: 2005-09-12
Posts: 1

Integration by substitution

hey im in college level calc and i am wondering if you could help me with this problem

∫2x^2/(2x^2+1) dx

thx for all your help

Offline

#2 2005-09-13 18:31:22

seiya_001
Member
Registered: 2005-08-23
Posts: 19

Re: Integration by substitution

I hope this helps...
your problem is:
∫2x^2/(2x^2+1) dx

divide 2x^2/(2x^2+1) to acquire 1-(1/2x^2+1)

then: ∫ 1-(1/2x^2+1) dx = ∫dx - ∫(1/2x^2+1) dx, yay..an easier integration...!!
                                    = x-∫(1/2x^2+1) dx, and we know that ∫1/(u^2+a^2) dx = 1/a arc tg u/a
thus: x- (arc tg x√2) or x(1-arc tg √2) + C

guys please CMIIW...


"If you can't have more age in your life, then have more life in your age..

Offline

Board footer

Powered by FluxBB