Question

Diberikan suku ke-2 barisan geometri = √x dan suku ke-5 = x√x. Tentukan:
a. U7
b. U10

Answer 1

U5=ar^4=x√x
u2=ar=√x

r³=x
r=∛x

maka a=x^(1/3)

U7=x^(1/3).(x^(2/3))^6=x^(1/3).x^4=x^(7/3)

U10=x^(1/3).(x^(2/3)^9=x^(1/3).x^6=x^(19/3)

Answer 2

U2=ar = √x
u5=ar^4= x√x

r^3 =x√x :  √x = x
r= x^1/3

ar = √x
a .x^1/3 = x^1/2
a = x^(1/2) / x^(1/3)
a = x^(1/2) . x^(-1/3)
a = x ^(3/6) . x^(-2/6)
a=x^(1/6)

u7= ar^6
    = x^(1/6) . r^3.r^3
    = x ^(1/6) . x. x
    = x^(1/6) . x²
    = x (13/6) atau 

u10= ar^9 = x^(1/6) . x^3
               = x^(1/6) . x^18/6
                = x^(19/6) =