Recent content by Renzokuken

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    Determining if sets are in the subspace

    Is this enough proof to show that B is not a subspace of R^2?
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    Determining if sets are in the subspace

    There exist some a ,b, A, B such that it is not in B. a+b is (x1^2+x2^2+y1^2+y2^2)<=1, which is not always true. ca is not in B because a=(.5,.5) and c=10 100(.5^2+.5^2) is greater then 1 so ca is not in B.
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    Determining if sets are in the subspace

    I think i am starting to understand it more. A(x1^2+x2^2)+B(y1^2+y2^2)<=1 where A and B are scalers a+b is not in B ca is not in B either since c can be a scaler that makes a not a subspace in B so B is not a subspace of R^2
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    Determining if sets are in the subspace

    If you have vectors a = (x1, y1) and b = (x2, y2) that are in B, will a + b also be in B? a=x1^2+y1^2<=1 0^2+0^2<=1 b=x2^2+y2^2=1 0^2+0^2<=1 a+b<=1 If you have a vector a = (x1, y1) that is in B, will any scalar multiple of it also be in B? a^2(x^2+y^2)<=1 if x and y are equal to 0 or a=0, then...
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    Determining if sets are in the subspace

    Homework Statement is B in subspace R^2 B=[x] :x^2+y^2<=1 [y] Homework Equations 1.0∈B 2.if u,v∈B u+v∈B 3.if u∈A a∈B then au∈B The Attempt at a Solution The <= is confusing me. I am not sure if i am suppose to treat it like an equal sign, or is it automatically not in the...
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    Integrating h(x,y) Over a Triangle

    1. Homework Statement Integrate h(x,y)=yi - xj over the triangle with vertices (-2,0), (2,0), (0,2) tranversed counterclockwise 2. Homework Equations (1-t)a+tb 3. The Attempt at a Solution (1-t)(-2,0)+t(2,0)=(-2+4t,0) (1-t)(2,0)+t(0,2)=(2-2t,2t) (1-t)(0,2)+t(-2,0)=(-2t,2-2t) integral y-x...
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    Solving Transfer of Energy: Find Height Dropped for Bowling Ball

    Is there a formula to find how much energy it takes for 5g of ice to melt?
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    Solving Transfer of Energy: Find Height Dropped for Bowling Ball

    1. Homework Statement An 11 kg bowling ball at 0 degrees C is dropped into a tub containing a mixture of ice and water. A short time later, when a new equilibrium has been established, there are 5.0 g less ice. From what height was the ball dropped? Assume that no water or ice splashes out...
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    Calculating Moles of Oxygen in a Cylinder

    ok i get it, i didnt see the gas part. It was talking about O2 thanks
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    Calculating Moles of Oxygen in a Cylinder

    [SOLVED] Converting Mol 1. A 20-cm-diameter cylinder that is 40 cm long contains 50 g of oxygen gas at 20 degrees celsius. How many moles of oxygen are in the cylinder? so 1 mol = 6.022*10^23 oxygen atomic mass=16g/mol 50g/16(g/mol) = 3.125 mol I don't know why it is wrong...
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    Double Integration with Polar Coordinates

    1. Integrate f(x,y)=x+y 1<=x^2+y^2<=4, x>=0, y>=0 3. ∬x+y dxdy x=rcos(o) y=rsin(o) ∬r(rcos(o)+rsin(o))drdo r is from 1 to 4, o is from 0 to pi/2 I get the wrong answer and don't know why
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    Double Integration of 4-y^2 in Bounded Region

    1. ∬(4-y^2 )dxdy bounded region between y^2=2x and y^2=8-2x I took the integral 4-y^2 dx and got 4x-xy^2 from 0-4 = 16-4y^2 then I took the integral 16-4y^2 dy from -2-2 = 128/3 It is wrong and I don't know what to do.
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    What Are the Optimal Dimensions for a Tank to Minimize Metal Usage?

    1.A petrochemical company is designing a cylindrical tank with hemispherical ends to be used in transporting its products. If the volume of the tank is to be 10,000 cubic meters what dimensions should be used to minimize the amount of metal required? 2. V=pi*r^2 + 4/3*pi*r^3 SA=...
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