Sorry. That's Croatian notation. I think american would be Volume=1/3*B*h where B is area of the base and h is height of tetrahedron. I can calculate h from formula for distance between point where first three planes intersect and the fourth plane. I don't know how to calculate area of the base...
Homework Statement
I have to find volume of tetrahedron that is bounded between 4 planes.
Planes are
x+y+z-1=0
x-y-1=0
x-z-1=0
z-2=0Homework Equations
\vec{a}=\vec{AB}=(X2-X1)\vec{i}+(y2-y1)\vec{j}+(z2-z1)\vec{k}
\vec{b}=\vec{AC}=(X2-X1)\vec{i}+(y2-y1)\vec{j}+(z2-z1)\vec{k}...
Homework Statement
Hi. I know this is a simple problem but i want to know if I am correct. Here it goes.
Body moves with speed 12 m/s. It starts to slow down with negative acceleration 2 m/s^{}2 for 8 meters. What is his speed after those 8 meters.Homework Equations
s=(1/2)*a*t*t
v*v=2as
v=v'...
Thank you for your help. I had math today. Teacher said it is okay. I supposed that vectors AC and BD are not parallel. I got one point in math with this question.
I still don't get it. Is there any other way in proving this? I just have to put this ("If AB and CD are parallel, then AB=r*CD for some r so the eqn becomes s*r*CD+t*CD=0 or s*r+t=0 or s=-t/r. For every t there is a corresponding solution for s.") in my textbook?
This seems logic to me. What happens if AB and CD are parallel? What are the solutions then? What kind of notion do I have to put in my problem so it will be correct?
I try to it but I can't get to the solution. I did this "AS=tAC, SC=(1-t)AC, BS=sBD, SD=(1-s)BD. Now put those into AS+SD=BS+SC and AS+SB=DS+SC." I get these 2 equations:
tAC - sBD = (s-1)BD + (1-t)AC
tAC +(1-s)BD = sBD + (1-t)AC
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then I multiply second equation with...
I only used this equation AS+SD=BS+SC. I put these formulas into it: AS=tAC, SC=(1-t)AC, BS=sBD, SD=(1-s)BD and I got this:
2tAC - 2sBD + BD - AC = 0
2tAC - 2sBD = AC - BD
Now in order equation to be correct it must be
2t = 1 and -2s = -1 (is this correct way to do this?)
From there...
Vector proof that diagonals of rhomb split in ratio 1/2.
[SIZE="2"][SIZE="4"]Homework Statement
Hi. For my math homework I have to prove with vectors(we are currently learning that) that diagonals of any rhomb split in half in ratio 1/2.
Homework Equations
A,B,C,D are end points of...
Homework Statement
I have to calculate disctance that body(for example a jumper) that jumps of a slope at 45 degrees with initial speed of 20 m/s and under 15 degrees.
Homework Equations
x=Vox * t
y=Voy*t - 1/2*g*t*t
y=ax + b, b=0 => y=ax
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The Attempt at a Solution
I don't know where to...