3ª tarea 1-4 7/09/10

1-.-25 -23 -21 -19 -17 -15 -13 -11 -9 -7 -5 -3.

2-R= -84/27…..-198/81….-432/243….-810/729….-972/2187…

-1458/6561….8748/19683…65610/59049….314928/117147.

3-.R= 63.25    59.5    55.75    52   48.25    44.5    40.75    37 3   3.25   29.5

4-.R= 115.8 103.45 91.1 78.75 66.4 54.05 41.7

5-.R= 54/7 45/7 36/7 27/7 18/7  9/7  0/7  -9/7   -18/7   -27/7   -36/7  -45/7


6-.(a1+ an)n/2   = (-3+187)-75/2


(-3+187)-75/2 = (184)-75/2 = 13800/2= 6900


R= 6900.

7-(a1+an)n/2    = (2+215) 164/2


(2+215) 164/2= (217) 164/2= 35588/2 = 17794


R= 17794. 

8-(a1+an)n/2      =(21+276)321/2

(21+276)321/2 = (297) 321/2 = 95337/2 = 47668.5


R= 47668.5

9-a1+d (n-1)      =-78+-49 (n-1)

-78+-49(n-1) =-127(n-1)


(n-1) = -127


n= -127+1


n= -128

10-. a1+d(n-1)   =    345+-169 (n-1)

345+-619 (n-1) = 176 (n-1)


(n-1) = -176


n= -176+1


n= -177