Question

seja   a p.a. (a1,a2,a3,...), com a, = -16 ea2 = -13. calcule a razao de cada p.a. a) (a1,a3,a5) b) ( a2,a4,a6...)

Answer 1

a, = -16 e a2 = -13

a1 + 1.r = a2 ==> -16 + r = - 13 ==> -13+16 ==> r = 3
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a) (a1,a3,a5) ==> ( - 16, - 10, - 4 )

a1 = - 16

a3= a1+2r==> -16+2.3= - 16+6 = - 10

a5=  a1+4r==> -16+4.3= - 16+12 = - 4
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b) ( a2,a4,a6...)    ( - 13, - 7, - 1 )

a2 = - 13

a4=  a1+3r==> -16+3.3= - 16+9 = - 7

a6=  a1+5r==> -16+5.3= - 16+15 = - 1
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