• Congratulations to the Class of 2024 on your results!
    Let us know how you went here
    Got a question about your uni preferences? Ask us here

Pi On A Calculator (1 Viewer)

Absolutezero

real human bean
Joined
Nov 17, 2007
Messages
15,077
Gender
Male
HSC
N/A
Throughout high school I used a fairly standard CASIO calculator, which had a scene which could hold up to around 70 digits when entering equations. However, answers also rounded to 9 decimal points. Hence, "Pi =" yielded the answer:

3.141592654

Does this mean if I used a closer approximation of Pi when I enter the equations, say "3.1415936535897932" it will be more accurate? Or, does the calculator estimate Pi to the full 70 places available? Or More?
 

Fortify

♪웨딩드레스
Joined
Mar 20, 2007
Messages
1,281
Gender
Male
HSC
2009
No it does not; I think it rounds off the number once its past 10 digits. So 3.1415926535... will round to what "Pi" is set on the calculator (3.141592654).
 

Absolutezero

real human bean
Joined
Nov 17, 2007
Messages
15,077
Gender
Male
HSC
N/A
Of course, because any answer given is only available to be given to 10 places.
 

Fortify

♪웨딩드레스
Joined
Mar 20, 2007
Messages
1,281
Gender
Male
HSC
2009
That is true; unless you have a calculator which will display more than 10 numbers otherwise there's not much anyone can do about it.
 

kurt.physics

Member
Joined
Jun 16, 2007
Messages
840
Gender
Undisclosed
HSC
N/A
Does this mean if I used a closer approximation of Pi when I enter the equations, say "3.1415936535897932" it will be more accurate? Or, does the calculator estimate Pi to the full 70 places available? Or More?
No... because pi is 3.1415926535897932 =P
 

Templar

P vs NP
Joined
Aug 11, 2004
Messages
1,979
Gender
Male
HSC
2004
For standard CASIO calculators with 12 digit mantissa (display) the memory stores 15 digits, so the calculator does store more than it can display, but not to the extent of 70 digits. This is to avoid rounding errors in most cases.

Having accurate up to the 10th decimal place is already sufficient for practically all physical applications. It means being able to calculate the circumference of the earth to the exact centimetre.
 

Absolutezero

real human bean
Joined
Nov 17, 2007
Messages
15,077
Gender
Male
HSC
N/A
No... because pi is 3.1415926535897932 =P
Purely a typographical error. :D I know it to more than I posted.

already sufficient for practically all physical applications.
True. I was just coming at it from a pure "Appreciating the Beauty and Elegance" perspective. :)
 

Templar

P vs NP
Joined
Aug 11, 2004
Messages
1,979
Gender
Male
HSC
2004
True. I was just coming at it from a pure "Appreciating the Beauty and Elegance" perspective. :)
Then , since you can never express it in decimal form. You should always use the symbol rather than 3.14159...:p
 

pman

Banned
Joined
Apr 7, 2009
Messages
2,127
Location
Teh Interwebz
Gender
Male
HSC
2009
if you have pi to 15 DP you can calculate the diameter, radius or circumference of any circle (no matter how large) to within one hydrogen atoms size, so realisticly, 10 dp is all you need
 

annabackwards

<3 Prophet 9
Joined
Jun 14, 2008
Messages
4,670
Location
Sydney
Gender
Female
HSC
2009
if you have pi to 15 DP you can calculate the diameter, radius or circumference of any circle (no matter how large) to within one hydrogen atoms size, so realisticly, 10 dp is all you need
Cool fact ^^
 

Fortify

♪웨딩드레스
Joined
Mar 20, 2007
Messages
1,281
Gender
Male
HSC
2009
3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679821480865132823066470938446095505822317253594081284811174502841027019385211055596446229489549303819644288109756659334461284756482337867831652712019091456485669234603486104543266482133936072602491412732458700660631558817488152092096282925409171536436789259036001133053054882046652138414695194151160943305727036575959195309218611738193261179310511854807446237996274956735188575272489122793818301194912983367336244065664308602139494639522473719070217986094370277053921717629317675238467481846766940513200056812714526356082778577134275778960917363717872146844090122495343014654958537105079227968925892354201995611212902196086403441815981362977477130996051870721134999999837297804995105973173281609631859502445945534690830264252230825334468503526193118817101000313783875288658753320838142061717766914730359825349042875546873115956286388235378759375195778185778053217122680661300192787661119590921642019893809525720106548586327886593615338182796823030195203530185296899577362259941389124972177528347913151557485724245415069595082953311686172785588907509838175463746493931925506040092770167113900984882401285836160356370766010471018194295559619894676783744944825537977472684710404753464620804668425906949129331367702898915210475216205696602405803815019351125338243003558764024749647326391419927260426992279678235478163600934172164121992458631503028618297455570674983850549458858692699569092721079750930295532116534498720275596023648066549911988183479775356636980742654252786255181841757467289097777279380008164706001614524919217321721477235014144197356854816136115735255213347574184946843852332390739414333454776241686251898356948556209921922218427255025425688767179049460165346680498862723279178608578438382796797668145410095388378636095068006422512520511739298489608412848862694560424196528502221066118630674427862203919494504712371378696095636437191728746776465757396241389086583264599581339047802759010
 
Last edited:

Uncle

Banned
Joined
Feb 5, 2009
Messages
3,265
Location
Retirement Village of Alaska
Gender
Male
HSC
2007


BOOM

Your calculator doesn't know what a
sine, cosine, tan, log, exponential, sinh, cosh, tanh or Pi is.
They use a secret called "Taylor's Polynomial".
Because the display can only display up to 10 to 12 digits, they can use sufficient terms to approximate the function to minimise the error and the values appear as if it were exactly the function itself.

Thanks UNSW MATH1231

Pi is exactly 3!
Scientists: *gasp*
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top