Why e, the Transcendental Math Constant, Is Just the Best

Nov 30, 2021 | Location Kirkwood

Why e, the Transcendental Math Constant, Is Just the Best

The solution to our puzzle about Euler’s number explains why e pops up in situations that involve optimality.


November 24, 2021

Last month, we presented three puzzles that seemed ordinary enough but contained a numerical twist. Hidden below the surface was the mysterious transcendental number e. Most familiar as the base of natural logarithms, Euler’s number e is a universal constant with an infinite decimal expansion that begins with 2.7 1828 1828 45 90 45… (spaces added to highlight the quasi-pattern in the first 15 digits after the decimal point). But why, in our puzzles, does it seemingly appear out of nowhere?

Before we attempt to answer this question, we need to learn a little more about e’s properties and aliases. Like its transcendental cousin πe can be represented in countless ways — as the sum of infinite series, an infinite product, a limit of infinite sequences, an amazingly regular continued fraction, and so on.

I still remember my first introduction to e. We were studying common logarithms in school, and I marveled at their ability to turn complicated multiplication problems into simple addition just by representing all numbers as fractional powers of 10. How, I wondered, were fractional and irrational powers calculated? It is, of course, easy to calculate integer powers such as 102 and 103, and in a pinch you could even calculate 102.5 by finding the square root of 105. But how did they figure out, as the log table asserted, that 20 was 101.30103? How could a complete table of logarithms of all numbers be constructed from scratch? I just couldn’t imagine how that could be done.

Later I learned about the magic formula that enables this feat. It gives a hint of where the “natural” in “natural logarithms” came from:

ex = 1 + x1!+x22!+x33!+x44!+x55!+⋯.

For negative powers, alternate terms are negative as expected:

e-x = 1 – x1!+x22!x33!+x44!x55!+⋯.

These powerful formulas enable the calculation of any power of the mysterious e for any real number, integer or fraction from negative infinity to infinity, to any desired precision. They allow the construction of a complete table of natural logarithms and, from that, common logarithms, from scratch.

The special case of this formula for x = 1 gives this famous representation of e:

e = 1 + 11!+12!+13!+14!+15!+⋯.

In addition, e has many amazing properties, some of which we’ll uncover in the solutions to our problems.

To continue reading this article, click here.

Locations near
ME
Ashburn 0.93 mi
43330 Junction Plaza
#160
Ashburn, VA 20147
Sterling 4.07 mi
44 Pidgeon Hill Drive
#100
Sterling, VA 20165
Leesburg 5.69 mi
521 E Market St
#B
Leesburg, VA 20176
Herndon 7.66 mi
2465 Centreville Road
#J2
Herndon, VA 20171
Stone Ridge 7.88 mi
42020 Village Center Plaza
#100
Stone Ridge, VA 20105
Reston 8.62 mi
1424 North Point Village Center
Reston, VA 20194
Purcellville 12.72 mi
1020 E Main St
Ste L
Purcellville, VA 20132
North Potomac 13.58 mi
12150 Darnestown Rd
Gaithersburg, MD 20878
Centreville 14.52 mi
5959 Centreville Crest Ln
Centreville, VA 20121
Fairfax 14.67 mi
11891 Grand Commons Ave
Fairfax, VA 22030
Potomac 14.98 mi
10232 River Road
#B
Potomac, MD 20854
Germantown MD 15.03 mi
12800 Middlebrook Road
Germantown, MD 20874
Tysons 15.45 mi
328 Maple Ave E
#A
Vienna, VA 22180
Haymarket 17.87 mi
15125 Washington St
Haymarket, VA 20169
Rockville 18.19 mi
20 Courthouse Square
#106
Rockville, MD 20850
Mclean 18.23 mi
1320 Old Chain Bridge Road
Suite #190
McLean, VA 22101
Gaithersburg 18.71 mi
9132 Rothbury Drive
Gaithersburg, MD 20886
North Bethesda 20.42 mi
5268 Nicholson Ln
#N
Kensington, MD 20895
Falls Church 20.59 mi
6674 Arlington Blvd
Falls Church, VA 22042
Manassas 20.65 mi
9722 Liberia Ave
Manassas, VA 20110
Bristow 20.71 mi
12705 Braemar Village Pz
Bristow, VA 20136
Burke 20.82 mi
9411 Old Burke Lake Rd
#C
Burke, VA 22015
Bethesda 21.3 mi
4918 Fairmont Ave
Bethesda, MD 20814
Annandale 21.64 mi
7000 Columbia Pike
Annandale, VA 22003
Damascus 22.77 mi
9815 Main St
Damascus, MD 20872
Arlington, VA 23.29 mi
4801 1st St N
Arlington, VA 22203
Cathedral Heights 23.51 mi
3706 Macomb St NW
Washington, D.C., DC 20016
Olney 23.96 mi
18157 Village Center Dr
Olney, MD 20832
Downtown Silver Spring 24.94 mi
1133 East West Highway
Silver Spring, MD 20910
Lorton 25.06 mi
9027 Silverbrook Rd
#A
Fairfax Station, VA 22039
West Washington 25.69 mi

Washington, DC 20009
Alexandria City 25.7 mi
4605 Duke Street
Alexandria, VA 22304
Lake Ridge 26.5 mi
12473 Dillingham Square
Lake Ridge, VA 22192
Frederick North 26.7 mi
905 W. 7th Street
Frederick, MD 21701
Northern Silver Spring 26.75 mi
732 Cloverly Street
Silver Spring, MD 20905
Alexandria 27.17 mi
6483 Old Beulah Street
Alexandria, VA 22315
Warrenton 27.42 mi
512 Fletcher Drive
Warrenton, VA 20186
Mount Airy 28.24 mi
411 E Ridgeville Blvd
Mt Airy, MD 21771
Capitol Hill DC 28.48 mi
621 Pennsylvania Ave SE
1st-floor unit
Washington, DC 20003
Dale City 28.99 mi
5512 Staples Mill Plaza
Dale City, VA 22193
Mount Vernon 29.66 mi
7696 H Richmond Hwy
Alexandria, VA 22306
Beltsville 30.89 mi
10914 Baltimore Ave
#B
Beltsville, MD 20705
Clarksville 31.56 mi
12250 Clarksville Pike
#D
Clarksville, MD 21029
Laurel 35.02 mi
10095 Washington Blvd N
#136
Laurel, MD 20723
Woodmore 35.27 mi
9101 Woodmore Centre Drive
Lanham, MD 20706
Glenn Dale 35.83 mi
10559 Greenbelt Rd
Lanham, MD 20706
Sykesville 36.57 mi
1207 Liberty Rd.
#D-104
Sykesville, MD 21784
Ellicott City 37.11 mi
3290 Pine Orchard Lane
#B
Ellicott City, MD 21042
Winchester 37.62 mi
2512 S Pleasant Valley Rd
Winchester, VA 22601
Columbia 38.19 mi
8827 Centre Park Drive
#F
Columbia, MD 21045
Stafford 39.58 mi
263 Garrisonville Road
#104
Stafford, VA 22554
Bowie 41.26 mi
15231 Hall Rd
Bowie, MD 20721
Waldorf 42.24 mi
3022 Festival Way
Waldorf, MD 20601
Crofton 42.6 mi
1153 Route 3 North
#120
Crofton, MD 21054
Owings Mills 44.15 mi
9433 Common Brook Rd #100
Owings Mills, MD 21117
Pikesville 46.84 mi
1433 Reisterstown Rd
Pikesville, MD 21208
Dunkirk 49.92 mi
10735 Town Center Blvd
#7
Dunkirk, MD 20754