Define 'cross-section' in the context of volumes.

A two-dimensional shape formed by slicing a three-dimensional solid.

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Define 'cross-section' in the context of volumes.

A two-dimensional shape formed by slicing a three-dimensional solid.

What is $A(x)$ in the volume formula?

Area of the cross-section perpendicular to the x-axis at a given x.

Define the term 'solid of revolution'.

A 3D solid formed by rotating a 2D shape around an axis.

What does ' $dx$ ' represent in the volume integral?

Infinitesimally small thickness of the cross-section.

What is the significance of the interval $[a, b]$ ?

The limits of integration, defining the region's boundaries.

Define the term 'volume'.

The amount of three-dimensional space occupied by an object.

What is the formula for the area of a square?

Area of a square is $s^2$ , where s is the side length.

What is the formula for the area of a rectangle?

Area of a rectangle is $w*h$ , where w is the width and h is the height.

What is the meaning of 'perpendicular'?

Intersecting at or forming right angles (90 degrees).

Define 'definite integral'.

Integral evaluated between specific upper and lower limits, resulting in a numerical value.

How does the graph of $A(x)$ relate to the volume of the solid?

The area under the curve of $A(x)$ from $a$ to $b$ represents the volume of the solid.

Given the graph of two functions, how can you identify the region that forms the base of the solid?

The region is enclosed between the two curves within the given interval [a, b].

How can you graphically determine the bounds of integration?

Find the x-coordinates (or y-coordinates if integrating with respect to y) of the intersection points of the bounding curves.

If the graph shows cross-sections perpendicular to the y-axis, what does this imply about the integration?

The integration must be performed with respect to y, and the functions must be expressed in terms of y.

How does a steeper slope in the graph of a bounding curve affect the volume of the solid?

A steeper slope can increase the area of the cross-sections, potentially increasing the volume of the solid.

How does the area between two curves on a graph relate to the side length of a square cross-section?

The area between the curves at a given x-value represents the side length 's' of the square cross-section at that x-value.

If the graph of $A(x)$ is always positive, what does this imply about the volume?

The volume will always be positive since we are summing positive areas.

How can you visually estimate the volume of the solid from the graph of $A(x)$ ?

Approximate the area under the curve of $A(x)$ using geometric shapes or numerical methods.

What does it mean if the two curves bounding the region intersect only at one point?

That point defines one of the limits of integration; you may need another boundary to fully define the region.

How can you use a graph to check if you've correctly identified which curve is 'above' or 'to the right'?

Visually confirm that the identified curve is indeed above (for x-axis) or to the right (for y-axis) of the other curve within the integration interval.

Volume of a solid with known cross-sections.

$V = \int_a^b A(x) dx$

Volume of a solid with square cross-sections.

$V = \int_a^b s^2 dx$

Volume of a solid with rectangular cross-sections.

$V = \int_a^b w cdot h dx$

Area of a square.

$A = s^2$

Area of a rectangle.

$A = w cdot h$

How do you find the side length 's' of a square cross section when given two bounding curves f(x) and g(x), where f(x) is above g(x)?

$s = f(x) - g(x)$

How do you find the width 'w' of a rectangular cross section perpendicular to the y-axis when given two bounding curves f(y) and g(y), where f(y) is to the right of g(y)?

$w = f(y) - g(y)$

How to find the intersection points of two curves, $f(x)$ and $g(x)$ ?

Set $f(x) = g(x)$ and solve for $x$ .

If integrating with respect to 'y', what does the volume formula become for general cross sections?

$V = \int_c^d A(y) dy$

How do you express $y = x^3$ as a function of y?

$x = \sqrt[3]{y}$