Question

40 PONTOS!!!!!!!!!!!!!!!!!!! P.G URGENTE.


soma dos 6 primeiros termos da pg,

A)(96,-48,24,...)
B)(-54,-48,-6,-2)
C)(12,3,3/4,...)

Answer 1

a1 = 96
a2 -48
a3 = 24
q = -48/96 =  - 1/2 ***
S6 =96 [ ( -1/2)⁶ - 1 ]/ (-1/2 - 1/1)
S6 = 96 [ 1/64 -1/1] / ( -3/2)a1 = -54
a2 =
S6 = 98 [ -63/64]/ (-3/2 )
S6 = 98 [( -63/64 ): ( - 3/2)] = 98 [ ( -63/64) * ( - 2/3)] = 
98/1 . ( 126/192 )  =  12348/192   = 1029/16 ****
b
a1 = -54
a2 =-48
q = -48/-54  = 8/9 ***
S6 =  ( -54) [ ( 8/9)⁶ - 1/1]/ ( 8/9 - 1/1)
S6 = ( - 54 ) [ ( 262144/531441 - 1/1 ] /( - 1/9)
S6  = ( - 54) [ - 269297/531441] /   ( - 1/9)
S6 =  -54/1 * ( - 269297/531441) * ( - 9/1)
S6 =  - 130878342/531441****

c
a1 = 12
a2 = 3
q = 3/12 =  1/4 ****
S6 = 12 [ (1/4)⁶ - 1/1]/ ( 1/4 - 1/1)
S6 = 12 [ ( 1/4096) - 1/1] / ( -3/4)
S6 = 12 [ (- 4095/4096] / ( - 3/4)
S6 =  12/1 * ( - 4095/4096) * ( - 4/3 )
S6 = 196560/12288  =  4095/256