Et $r = \zz[\sqrt{-n}]$ where $n$ is a squarefree integer $> 3$. prove that $2$, $\sqrt{-n}$, and $1 + \sqrt{-n}$ are all irreducible in $r$. \item prove that $r$ is not a ufd. [hint: show that either $\sqrt{-n}$ or $1+\sqrt{-n}$ is not prime.] \item find a non-principal ideal in r.

50

step-by-step explanation:

answer: cos [   arcsin (3/5) - arccos (1/2) ] =

step-by-step explanation: × = 3/5 = 0.6--> x = 36.87 and x = 180 - 36.87 = 143.13 deg

cos y = 1/2 --> y = +- 60 deg a. cos (x - y) = cos (143.13 - 60) = cos 83,13  

=

0.12

b. cos (36.87 - 60) = cos (-23.23) = 0.92

answer:

some responsibilities that come with having a checking account -

1. we have to maintain check register with exactness to avoid checks being returned for insufficient funds which is called bouncing a check.

2. we need to update our check register each time we make a transaction using a convenience card. updating check register will   save   us from   overdrawing of checking account.

3. read the agreement the bank gave you when you signed up for our checking account. this includes all the fees and the minimum balance we need to keep in our account to avoid maintenance charges.  

explanation:

note : -   checking account is a transactional deposit account. we can use it to deposit and withdraw funds. money in a checking account is very liquid. it   can be withdrawn using electronic debits, automated cash machines, or checks among other methods.