Recent content by tomfrank

i try but i don't really know how to get the value of V out.

about now...?

so just to understand, I solve for t and for the x equation and plug into the other one, so that I can eliminate t and I got. v = sqrt((1/2)*sqrt(2)*sqrt((2*sin(theta)^4-2+3*cos(theta)^2)*cos(theta)*h*g*(sin(theta)+cos(theta)))/(2*sin(theta)^4-2+3*cos(theta)^2)) now I take the derivative...

so i correct the equation put it in the t. By solving for V i got V = (1/2)*g*t/(cos(theta)-sin(theta)) if I differentiate w.r.t. theta and set it = to 0 I got theta = -pi/4 is that right, how do i get the speed?

Homework Statement So the goal is to reach a distance H in the x-direction, starting from a height H in the y-direction, and you need to minimize the speed, and find the smalest and angle. Homework Equations i did: dx = V cos(theta) *t and y = y_0 +V sin(theta)*t-1/2*g*t^2 Vx =...

it means the magnitude, i believe.

Homework Statement Calculate ||1,1,1||in R3 Calculate ||1,1,1,1|| in R4. Calculate ||1,1,...,1|| in Rn. Homework Equations All I have in this problem is that, Where do I start? The Attempt at a Solution

so if i split the 2 function apart... the e^-x approach '0' but the sin(x) approach nothing it will keep going from -1 to 1 right?

Is there any other reason why it goes to zero?

Homework Statement I am trying to take the following limit lim as x goes to infinity of ( e^-x )*sin(x) Homework Equations The Attempt at a Solution Can I say that it ges to '0' just because the 1/e^x goes to '0'. Or there is a better way to solve it?

that looks nice thanks

So the first one domain = R^2 the real plane second one = is y+z not equal to '0' is that right?

so for the first one can just do from (-infinity to infinity) ? can i just put in any value of x i want to?

Homework Statement I am trying to find the domain of the following.. R^2 to R^3 of g(x,y) = (x-y,x+y,3*x) R^3 to R of h(x,y,z) = x/(y+z) Homework Equations The Attempt at a Solution I don't know how to start. I know how to find the domain in one dimension but how...

i got the problem..thanks bye