Recent content by shanshan

tried this - ended up with: [5v^2-2vsinx)^1/2]/2 and this still wasn't right. Do you see any other problems?

Homework Statement I need to simplify vf = [(vcosx/2)^2+((2v-vsinx)/2)^2)]^1/2 as far as possible Homework Equations The Attempt at a Solution vf = [(vcosx/2)^2+((2v-vsinx)/2)^2)]^1/2 = [(v^2cos^2(x)+v^2sin^2(x)+4v^2+2vsinx)/2]^1/2 = [(v^2(1)+4v^2-2vsinx)/2]^1/2 ---- using...

Homework Statement Two cars, both of mass m, collide and stick together. Prior to the collision, one car had been traveling north at speed 2v, while the second was traveling at speed v at an angle x south of east (as indicated in the figure). After the collision, the two-car system travels at...

.. Stupid question I'm sure, but I thought that you couldn't just square both sides of the equation? So when you square each term, it's okay? Thanks a bunch, I know that was a lot of work.. And i think my textbook probably has a mistake for the answer, i know it has before.

Okay. I had sqrt(2)/2 on my sheet as my answer, I guess I just typed it wrong. But Thankyou!

No, I haven't.. I asked my teacher what it was, and she said that I shouldn't try to teach it to myself, and that she wouldn't accept it on a test.. :S

Okay, I will keep that in mind for next time... But either way, I come out with the same answer, y = 4. I'm thinking maybe the answer key is wrong, I've done this question so many times!

Sorry, that's all the question's given me.. I know it's not really worded that well but I'd really appreciate your help... I'm going to assume from the types of question I've been doing that the road has to pass through the station. "so if S is the station, i assume you mean a = |AC| = 5 b =...

Homework Statement Find the dimensions of the largest rectangle with sides parallel to the axes that can be inscribed in the ellipse x^2 + 4y^2 = 4 Homework Equations The Attempt at a Solution I simplified the equation of the ellipse into the ellipse formula: x^2/4 + y^2 = 1...

Homework Statement Two towns, A and B are 5 km and 7 km respectively, from a railroad line. The points C and D nearest to A and B on the line are 6 km apart. Where should a station be located to minimize the length of a new road from A to B? Homework Equations a^2+b^2 = c^2, a=0.5bh(?)...

yes, these are the times listed on my sheet. there may be a typo though.

Homework Statement At ten am, a plane traveling east at 100km/hr is 500 km west of a jet traveling south at 200km/hr. At what rate is the distance between them changing at noon? Homework Equations The Attempt at a Solution 2aa' + 2bb' = 2cc' 2(300)(-100) + 2(400)(200) = (1000)c'...

ahhhh and the light goes on. thankyou!

but how can i use similar triangles if i only have one of the dimensions of the triangle?

AHHH silly mistake. thankyou!