Recent content by lemonlee

Homework Statement 2x^2+5xy-y^2=1 Homework Equations d/dx(f(u)x))=df/du * du/dx The Attempt at a Solution i got (2y-4x)/5x but I'm almost certain that its wrong...can anyone help me?

so if the equation that I'm trying to intergrate is F=-kx^4 i first have to find the derivative of -kx^4=4x^3 (right?) and then 4x^3dx=1/4x4+C and from there i put in the two values (d and 0) and subtract them to find the definite integral?

Homework Statement I've been trying to find a website to explain this to me, but I'm still confused as to how to do an integral. The one that I have been trying to figure out is this: Integral from 0 to d of F(x)dx i can't figure out where the integral sign is either...sorry! but 0 is on...

oh i see what i forgot, I didn't multiply by the mass, I was just solving for F=a... oops! thank you for explaining that :)

so I can assume that the net force is zero because the piano is accelerating, right? wouldn't that just make the force exerted by the man 4.45N? I think i might be missing a step

Homework Statement a 380 kg piano slides 3.9m down a ramp with an incline of 27* and is kept from accelerating by a man pushing parallel to the incline. Find the force exerted by the man, the work done by the man on the piano, the work done by the force of gravity, and the net work on the...