Question

PG URGENTE!!!!!

A)a1= - 1/4 q= -80 n = 5
B)a1= -1/6 q= 32 n= 5
C)a1=1/2 q= -22 n= 5

Answer 1

FÓRMULA da PG
an = a1.q^(n - 1)                ----> (^) simbolo de elevado

A)a1= - 1/4 q= -80 n = 5 

an = a1.q^(n - 1)
an = -1/4(-80)⁵⁻¹
an = -1/4(-80)⁴                         (1/4 = 0,25)
an = - 0,25(-80)⁴
an = + 0,25(80)⁴
an = 20⁴
an = 160.000


B)a1= -1/6 q= 32 n= 5

an = a1.q^(n- 1)
an = -1/6(32)⁵⁻¹
an = -1/6(32)⁴
an = (-1(32)/6)⁴
an = (- 32/6)⁴         ( divide AMBOS por 2)
an = (-16/3)⁴
an = + 16⁴/3⁴
an = 65.536/81

C)a1=1/2 q= -22 n= 5

an = a1.q^(n - 1)
an = 1/2(-22)⁵⁻¹
an = 1/2(-22)⁴                            ( 1/2 = 0,5)
an = 0,5(-22)⁴
an = (- 11)⁴
an = + 14.641