Объяснение:
{ b1 + b2 = b1 + b1*q = b1*(1+q) = 16
{ b2 + b3 = b1*q + b1*q^2 = b1*q*(1+q) = 36
Отсюда
16*q= 36; q = 36/16 = 9/4
b1 = 16/(1+q) = 16 : (1+9/4) = 16 : (13/4) = 64/13
Три первых члена:
b1 = 64/13; b2 = 64/13*9/4 = 144/13; b3 = 144/13*9/4 = 324/13
Объяснение:
{ b1 + b2 = b1 + b1*q = b1*(1+q) = 16
{ b2 + b3 = b1*q + b1*q^2 = b1*q*(1+q) = 36
Отсюда
16*q= 36; q = 36/16 = 9/4
b1 = 16/(1+q) = 16 : (1+9/4) = 16 : (13/4) = 64/13
Три первых члена:
b1 = 64/13; b2 = 64/13*9/4 = 144/13; b3 = 144/13*9/4 = 324/13