Integration of Trig Function- NEED HELP (1 Viewer)

[sando]

1/2
S pie x
0

 

[pLuvia]

pi is a constant so move it out

1/2
pi ∫ x dx
0

pi [x²/2]^1/2₀

= pi/8

 

[sando]

thanks... that makes it much easier to understand. I was tryin to work it out without takin pie out the front

 

[sando]

p.s. how do u write the S like that?

i've got mathtype but that only works for microsoft works

 

[Riviet]

I copy & paste the integration symbol from MS word.

 

[sando]

EDIT: MISWROTE QUESTION

QUESTION REALLY IS:

½
∫ sin pie x
0

 

[sando]

therefore i still need help, with the amended question

 

[SoulSearcher]

it would be

^1/2
∫ sin pi x dx = - [ (cos pi x) / pi ]^1/2₀
0

= - { [ (cos pi/2) / pi ] - [ cos 0 / pi ] }
= - { 0 - 1 / pi }
= 1 / pi units²

 

[sando]

correct. Thanks

If i hav any more questions on trig functions i will post them here.

U guys hav been great help

 

[Riviet]

QUESTION REALLY IS:

½
∫ sin pie x
0

Treat pi like a constant multiplied by x.

Remember that ∫ sin(ax) dx = [-cos(ax)]/a, where a is the constant.

 

[Trev]

You can write the integration symbol by typing & int ; without the two spaces, so ∫.

 

[pLuvia]

Or you could just Character map

 

[sando]

NEW QUESTION THAT I'M HAVING TROUBLE WITH:

Find, in exact form, the volume of the solid of revolution formed by rotating the curve y = √ sin 2x about the x-axis from x = 0 to x = pi/6

 

[Mountain.Dew]

NEW QUESTION THAT I'M HAVING TROUBLE WITH:

Find, in exact form, the volume of the solid of revolution formed by rotating the curve y = √ sin 2x about the x-axis from x = 0 to x = pi/6

dont be daunted by the square root sign. this involves solids of revolution, so the general formula for volume would be:

b
∫ pi * y^2 dx
a

in ur case, y^2 = (√ sin 2x)^2 = sin2x...tada!

so ur volume would be:

pi/6
∫ pi * sin2x dx
0

im sure u can work it out from there