Important: to denote exponentiation use " ^ ":
<span>(x + y)1 = ___ x + ___ y NO
</span><span>(x + y)^1 = ___ x + ___ y YES
(x+y)^1 = 1x + 1y
(x+y)^2 = 1x + 2xy + y^2
(x+y)^3 = 1x^3 + 3x^2*y + 3x*y^2 + y^3
and so on. Look up "Pascal's Triangle" if you want more info on this pattern.
*******************
</span><span>(x + y)4 = ___ x4 + ___ x3y + ___ x2y2 + ___ xy3 + ___ y4 NO
</span>
<span>(x + y)^4 = ___ x^4 + ___ x^3y + ___ x^2y^2 + ___ xy^3 + ___ y^4 YES
(x+y)^4 = 1x^4 + 4x^3*y + 6x^2*y^2 + 4x*y^3 + y^4</span>
I = PRT
P = 8000
T = 4
R = 12%...turn to decimal...0.12
now we sub
I = (8000)(0.12)(4)
I = 3840 <==
<span>Sphere: (x - 4)^2 + (y + 12)^2 + (z - 8)^2 = 100
Intersection in xy-plane: (x - 4)^2 + (y + 12)^2 = 36
Intersection in xz-plane: DNE
Intersection in yz-plane: (y + 12)^2 + (z - 8)^2 = 84
The desired equation is quite simple. Let's first create an equation for the sphere centered at the origin:
x^2 + y^2 + z^2 = 10^2
Now let's translate that sphere to the desired center (4, -12, 8). To do that, just subtract the center coordinate from the x, y, and z variables. So
(x - 4)^2 + (y - -12)^2 + (z - 8)^2 = 10^2
(x - 4)^2 + (y - -12)^2 + (z - 8)^2 = 100
Might as well deal with that double negative for y, so
(x - 4)^2 + (y + 12)^2 + (z - 8)^2 = 100
And we have the desired equation.
Now for dealing with the coordinate planes. Basically, for each coordinate plane, simply set the coordinate value to 0 for the axis that's not in the desired plane. So for the xy-plane, set the z value to 0 and simplify. So let's do that for each plane:
xy-plane:
(x - 4)^2 + (y + 12)^2 + (z - 8)^2 = 100
(x - 4)^2 + (y + 12)^2 + (0 - 8)^2 = 100
(x - 4)^2 + (y + 12)^2 + (-8)^2 = 100
(x - 4)^2 + (y + 12)^2 + 64 = 100
(x - 4)^2 + (y + 12)^2 = 36
xz-plane:
(x - 4)^2 + (y + 12)^2 + (z - 8)^2 = 100
(x - 4)^2 + (0 + 12)^2 + (z - 8)^2 = 100
(x - 4)^2 + 12^2 + (z - 8)^2 = 100
(x - 4)^2 + 144 + (z - 8)^2 = 100
(x - 4)^2 + (z - 8)^2 = -44
And since there's no possible way to ever get a sum of 2 squares to be equal to a negative number, the answer to this intersection is DNE. This shouldn't be a surprise since the center point is 12 units from this plane and the sphere has a radius of only 10 units.
yz-plane:
(x - 4)^2 + (y + 12)^2 + (z - 8)^2 = 100
(0 - 4)^2 + (y + 12)^2 + (z - 8)^2 = 100
(-4)^2 + (y + 12)^2 + (z - 8)^2 = 100
16 + (y + 12)^2 + (z - 8)^2 = 100
(y + 12)^2 + (z - 8)^2 = 84</span>
300 kelvin is greater.
300 kelvin equals approximately 26.85°C
