The paraboloid intersects the x-y plane when x²+y²=9, defining a circle with a radius of 3, centered at the origin.
<span>Utilizing cylindrical coordinates (r,θ,z), the paraboloid transforms into z = 9−r² and f = 5r²z. </span>
<span>If F represents the average of f over the area R then F ∫ (R)dV = ∫ (R)fdV </span>
<span>∫ (R)dV = ∫∫∫ [θ=0,2π, r=0,3, z=0,9−r²] rdrdθdz </span>
<span>= ∫∫ [θ=0,2π, r=0,3] r(9−r²)drdθ = ∫ [θ=0,2π] { (9/2)3² − (1/4)3⁴} dθ = 81π/2 </span>
<span>∫ (R)fdV = ∫∫∫ [θ=0,2π, r=0,3, z=0,9−r²] 5r²z.rdrdθdz </span>
<span>= 5∫∫ [θ=0,2π, r=0,3] ½r³{ (9−r²)² − 0 } drdθ </span>
<span>= (5/2)∫∫ [θ=0,2π, r=0,3] { 81r³ − 18r⁵ + r⁷} drdθ </span>
<span>= (5/2)∫ [θ=0,2π] { (81/4)3⁴− (3)3⁶+ (1/8)3⁸} dθ = 10935π/8 </span>
<span>Thus, F = 10935π/8 ÷ 81π/2 = 135/4</span>
Lengthwise count of 1/2-inch cubes = 8 1/2 ÷ 1/2 = 17
Widthwise count of 1/2-inch cubes = 5 1/2 ÷ 1/2 = 11
Heightwise count of 1/2-inch cubes = 2 1/2 ÷ 1/2 = 5
Total number of 1/2-inch cubes = 17 x 11 x 5 = 935
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Answer: 935 1/2-inch cubes are required.
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To address this issue, we will utilize the formula for determining the distance from a point to a line.
The formula is:
distance = | a x + b y + c | / sqrt (a^2 + b^2)
We have the line equation:
y = 2 x + 4
Rearranging it results in:
<span>y – 2 x – 4 = 0 -->
a = -2, b = 1, c = -4</span>
The coordinates given are:
(-4, 11) = (x, y)
Substituting into the distance formula:
distance = | -2 * -4 + 1 * 11 + -4 | / sqrt [(- 2)^2 + (1)^2]
distance = 15 / sqrt (5)
distance ≈ 6.7
<span>Thus, the tree is approximately 6.7 ft from the zip line.</span>
