Recent content by weckod

eval. double integal sprt(1+x^2+y^2)ds S is helicoid and r(u,v) = ucos(v)i+usin(v)j+vk, with 0 <=u<=4 and 0<=v<=4pi help please i don't know what a helicoid is!

thanks a lot dude! u helped a lot i hate cal 3 its just hard for me for some reasons... its the vectors... i can't picture them...

yay its just 1...

wow now the y(t) and z(t) is right but the x(t) is still wrong...

well x(t) is not 1+t and same w/the others.. the computer say its wrong... that's what trippin me out

so what is x(t)=? y(t)=? z(t)=? because i see what u did but the computer say its wrong... so i dontk now where it went wrong... i know what u did i did the same..

anyone know how to help here?

well i worked out the second one i got (1, 1) i really I am doing something stupid

I did that and the damn computer say i got the wrong answers... like the 1st one i took it derivative then i divid it by its magnitude which is squaring everything and sq rt it right that's what i did..

need parametric equations to the tangent line at the point (cos 0pi/6, sin 0pi/6, 0pi/6) on the curve x = cost, y = sint, z = t x(t) = ? y(t)=? z(t)=? now from my understanding, i have to find the derivatives of x, y, and z right? and i did this... now alll i should do is plug in the...

positon vectors r(t) find the unit tangent vectors T(t) for the given value of t r(t) = (cos5t, sin5t) T(pi/4) = ( , ) r(t) = (t^2, t^3) T(1) = ? r(t) = e^5t i + e^-1t j + t k T(2) = ? i+ ? j+ ? k now the to find it i use r'(t)/lr'(t)l I did that, but i get...

Hey thanks for the answer but how could u just take an x^2 + y^2 = cos(t)^2 + sin(t)^2 = 1 just like that?? im lookin athe parametrics and i see no sqs... how could u know its sqs and not like x^3 or something??

i have the parametric equations to the curve X = cos t y = sin t and z = t which of the following surfaces does it lie on? 1)circular cylinder 2)elliptic paraboloid 3)sphere 4)plane I think there's more than one answer but i can't seem to picture it from the equation on why. Anyone...