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 EdH 2021-09-01 02:10

[QUOTE=xilman;586957]So?

The formula is a correct expression for the area of the figure depicted.[/QUOTE]
Perhaps I'm confused as well. Are not three of the four formulas depicting volume?

Edit: I suppose you could call volume A if you wanted to. . .

 retina 2021-09-01 02:23

[QUOTE=EdH;586959]Are not three of the four formulas depicting volume?[/QUOTE]Reading the alt text might help to explain.

[spoiler]Geometry textbooks always try to trick you by adding decorative stripes and dotted lines.[/spoiler]

 xilman 2021-09-01 11:29

[QUOTE=EdH;586959]Perhaps I'm confused as well. Are not three of the four formulas depicting volume?

Edit: I suppose you could call volume A if you wanted to. . .[/QUOTE]No, all depict areas.

Simple dimensional analysis shows that the formulae all denoted areas. All products of lengths contain precisely two factors.

 EdH 2021-09-01 12:51

[QUOTE=EdH;586959]Perhaps I'm confused as well.
. . .[/QUOTE]Yep![QUOTE=retina;586960]Reading the alt text might help to explain.

[spoiler]Geometry textbooks always try to trick you by adding decorative stripes and dotted lines.[/spoiler][/QUOTE]I had read it. It hadn't helped.[QUOTE=xilman;586977]No, all depict areas.

Simple dimensional analysis shows that the formulae all denoted areas. All products of lengths contain precisely two factors.[/QUOTE]My limited analysis was to see "h" in the formulae. (I almost used this plural the first time, but, alas. . .)

 retina 2021-09-01 12:59

[QUOTE=EdH;586985]Yep!I had read it. It hadn't helped.[/QUOTE]Ignore all of the internal lines and stripes (the "decorations") and just consider the area of the outer shape.

 EdH 2021-09-01 13:09

[QUOTE=retina;586986]Ignore all of the internal lines and stripes (the "decorations") and just consider the area of the outer shape.[/QUOTE]Thank you - surface area of 3-D object, rather than volume of 3-D object! I was kind of thinking something wasn't quite correct for volume in the third example with pi*r/2.

 xilman 2021-09-01 13:20

[QUOTE=EdH;586987]Thank you - surface area of 3-D object, rather than volume of 3-D object! I was kind of thinking something wasn't quite correct for volume in the third example with pi*r/2.[/QUOTE]close, but no cigar.

None of the objects depicted are three-dimensional. They are just flat shapes annotated with superfluous lines, etc, to fool you into thinking that they represent 3-D objects.

The "cuboid" for instance, is just a rectangle with a rhombus adjoined to two of its sides. The "cone" is a triangle adjoined to a segment of a circle, and so on.

 EdH 2021-09-01 14:25

[QUOTE=xilman;586988]close, but no cigar.

None of the objects depicted are three-dimensional. They are just flat shapes annotated with superfluous lines, etc, to fool you into thinking that they represent 3-D objects.

The "cuboid" for instance, is just a rectangle with a rhombus adjoined to two of its sides. The "cone" is a triangle adjoined to a segment of a circle, and so on.[/QUOTE]I see it now (he says again). I've flattened all the figures and taken into account the ellipses and b being half the triangle base for the second. I "think" I now have it!

Thank you for the help. (And, especially, for pointing out that I must take the time to fully look at these to appreciate them.)

 firejuggler 2021-12-07 13:24

Nordic countries have the most impressive tourism add.