Answer: If the initial term of an arithmetic sequence is a 1 and the common difference of successive members is d, then the nth term of the sequence is given by: a n = a 1 + (n - 1)d The sum of the first n terms S n of an arithmetic sequence is calculated by the following formula: S n = n (a 1 + a n)/2 = n [2a 1 + (n - 1)d]/2
Derivitive of cosx=-sinx
dy/dx sinx=cosx
and use chain rue
2cosx=-2sinx
2cos2x=-4sin2x
so
-2sinx-4sin2x id the deritivitve
C.) 30 since they both have 5's just take them out then subtract 50 and 20 *but make sure u take out the decimal though* so after u subtract u will get 30 then line it up and put the decimal back then it will be .30
If you would like to know how many hours will Lena need to work before she can afford to buy the computer, you can calculate this using the following steps:
$900 - $473 = $427
$427 / $7 = 61 hours of yard work
Result: Lena will need to work 61 hours before she can afford to buy the computer.
