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1/2(1-cos2x) dx

2007-06-07 06:29:27 · 5 answers · asked by Anonymous in Science & Mathematics Mathematics

5 answers

(-sin(2x) + 2x)/4 + C

2007-06-07 06:33:23 · answer #1 · answered by MathGuy 6 · 1 1

write cos(2x) = 1 - 2sin^2 x
The denominator becomes
4*sin^2 x
so now you must integrate
1/4 * csc^2 (x)

That's a standard integral.
answer: -1/4 * cot(x) + constant

*EDIT*
This would of course be correct if hte 1-cos2x is in the denominator. The above answerer would be correct if it were inthe numerator. It's hard to tell from the way you wrote it.

2007-06-07 13:36:30 · answer #2 · answered by Dr D 7 · 0 2

it is really 2 integrals (B/C of addition/subtraction you can seperate them)
int of 1/2dx & int of -1/2 cos2xdx
1/2dx=> 1/2 X
-1/2 cos2xdx=> -1/2 * 1/2 sin2x = -1/4sin2x
which gives us=== 1/2x-1/4sin2x

2007-06-07 13:41:19 · answer #3 · answered by team 2 · 0 0

I = (1/2).∫(1 - cos 2x).dx
I = (1/2).x - (1/2) ∫ cos(2x).dx
let u = 2x
du/dx = 2
dx = du / 2
I = (1/2).x - (1/4).∫ cos u.du
I = (1/2).x - (1/4).sin u + C
I = (1/2).x - (1/4).sin 2x + C

2007-06-08 02:42:26 · answer #4 · answered by Como 7 · 0 0

=(1/2)x -(sin2x)/4

2007-06-07 13:33:45 · answer #5 · answered by Robin 4 · 0 0

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