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find the 8th geometric sequence which has for its 3rd and 6th terms are 1 and -64
a.-1024
b 2048
c.4096
d.3076​


Sagot :

Answer:

A

Step-by-step explanation:

a+2d = 7

a+5d =36

subtract them:

3d = 29

d = 29/3

then a + 58/3 = 7

3a + 58 = 21

a = -37/3

term(8) = a + 7d

= -37/3 + 7(29/3) = 166/3

check:

-37/3 , -8/3 , 7 , 50/3 , 79/3 , 36, 137/3, 166/3, ..