
By the fundamental theorem of calculus,

Now the arc length over an arbitrary interval

is

But before we compute the integral, first we need to make sure the integrand exists over it.

is undefined if

, so we assume

and for convenience that

. Then
Can you please take the pictures again I would love to help you! <3
Adding in base 3 is very much like adding in base 10, but instead of carrying digits when their sum exceeds 9, we have to watch for when the sum exceeds 2:
. 112
+ 210
- - - - -
. 322 -> 1022
. 12021
+ 2122
- - - - - - -
. 14143 -> 14150 -> 14220 -> 21220
. 20001
+ 1111
- - - - - - -
. 21112
. 120021
+ 2002
- - - - - - - -
. 122023 -> 122030 -> 122100
She must by 60 tiles for the prices to be even. 24+0.79x=1.19x x=amount of tiles. you subtract 0.79x from both sides. you should get 24=0.4x. then you divide 0.4 from both sides. you should get 60=x