Solving for intersections on the CAS calc

[Flaming_Arrow]

for eg

when i solve it just comes up as

[/0]

Whenever solving fails, graph it and find intersections or use nSolve(

[Flaming_Arrow]

whats nSolve?

[Flaming_Arrow]

u put ur calc in exact mode. change it to approximate

it's on auto

[wombifat]

what sort of calculator do you have?

[Flaming_Arrow]

ti-89 TIT CAS

[wombifat]

ok then no idea

[TrueTears]

for equations such as , using Solve on the calc will never give you an exact answer even if your calc is in exact mode. To find an approximate answer you must press 'green diamond' + enter to give a decimal answer. Or you can sketch the graph of both and find the intersection, again this will yield an approximate decimal answer.

[Flaming_Arrow]

nah i mean when i try solve it they just rearrange the functions, it doesnt give me an exact answer

[TrueTears]

nah i mean when i try solve it they just rearrange the functions, it doesnt give me an exact answer

yeah it's impossible to yield an exact answer using solve on the TI-89

[Mao]

This is because not all equations have elementary solutions (numbers that cannot be expressed with a finite number of elementary operations). In this case, to yield an approximate, press "Green" + "Enter" to approximate.

Althought sometimes it does that because there isn't a solution. Graphing is the best way to go imo.

[Flaming_Arrow]

when i press diamond + enter i get (2.71828)^x-0.5(x+1)=0

[TrueTears]

graph it and then use intersection ("F5 -> 5:")

[Flaming_Arrow]

graph it and then use intersection ("F5 -> 5:")

yer i know how to do it like that but i was wondering if you could directly to solve it to save time

[TrueTears]

for some reason sometimes the calc can not solve some equations. I often graph just to be safe.