Difficult Optimisation problem (maximizing a cuboid)

In summary, the conversation revolved around finding the optimal solution for maximizing a cuboid. The speaker suggests cutting the cuboid in half on the y-axis to simplify the problem. They discuss the dimensions of the resulting rectangle and how to find the area using calculus. The question of when the height will be at least 75% of the base is also raised. The conversation ends with the speaker mentioning the importance of staying within the boundaries of an ellipse when solving the optimization problem.
  • #1
don1231915
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Difficult Optimisation problem! (maximizing a cuboid)

Find derivate d(x)
 
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  • #2


Well, just cut in in half on the y-axis. The base of half your cuboid (... a rectangle or square in this case...) is just x. The height is 1296-x^2. We're looking on x=0 to 36, right? Well, almost. At what value of x is the height going to be at least 75% of the base? Then what's the area of this half rectangle? Can you find the optimum using calculus?
 
  • #3


Ok, it made it easier for me to think about but forget about what i said about cutting it in half.

If x were greater than 36, then you would be outside the ellipse, but you want to say inside.

Think of creating your rectangle using the variable x. If I set one corner at (x,0), then I can set another corner at (x, sqrt(1296-x^2)). So it has width 2x and height sqrt(1296-x^2). Therefore the area is ____ ?

Regarding the 75% thing - for what x will the height be exactly 75% of the width? Now for what values is it less than 75% of the width? Think that you want sqrt(1296-x^2) to be less than 75% of 2x.
 

1. How do you determine the optimal dimensions of a cuboid to maximize its volume?

To determine the optimal dimensions of a cuboid, we must first set up an optimization problem by defining the objective function, which in this case is the volume of the cuboid. Then, we use calculus and the first derivative test to find the critical points of the function. The critical points will give us the possible optimal dimensions for the cuboid. We can then use the second derivative test to determine if the critical points correspond to a maximum or minimum value. Finally, we can compare the values at the critical points to determine the optimal dimensions for maximizing the cuboid's volume.

2. What are the constraints when trying to maximize a cuboid's volume?

The constraints when maximizing a cuboid's volume are typically the fixed surface area or budget. This means that the total surface area of the cuboid must remain constant, or the cost of materials to construct the cuboid must not exceed a certain amount. These constraints limit the possible combinations of dimensions for the cuboid and must be taken into account when setting up the optimization problem.

3. How does the shape of a cuboid affect its maximum volume?

The shape of a cuboid does not affect its maximum volume as long as the dimensions satisfy the constraints. The optimal dimensions will always result in the maximum volume, regardless of the shape of the cuboid. However, different shapes may have different optimal dimensions, so it is important to consider the constraints and choose the appropriate shape that will result in the desired volume.

4. Can a computer program be used to solve a difficult optimization problem for maximizing a cuboid?

Yes, a computer program can be used to solve difficult optimization problems for maximizing a cuboid. By inputting the constraints and objective function, the program can use numerical methods to find the optimal dimensions and maximum volume. However, it is important to double-check the results and ensure that the program is set up correctly to avoid any errors in the solution.

5. Are there any real-world applications for optimizing the volume of a cuboid?

Yes, optimizing the volume of a cuboid has many real-world applications. For example, it can be used in architecture and construction to determine the dimensions of a building or room that will result in the maximum volume. It can also be used in packaging and manufacturing to determine the optimal size and shape of a product to minimize material waste and production costs. Additionally, it can be applied in engineering and design to optimize the dimensions of structures and objects for maximum efficiency and functionality.

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