Question

В геометрической прогрессии (yn) y3=3, y4=2,25. Найдите y2·y5.

Answer 1

q = y4/y3 = 2,25 : 3 = 9/4 : 3 = 9/4 * 1/3 = 3/4

y5 = y4 * q = 2,25 * 3/4 = 9/4 * 3/4 = 27/16

y2 = y3 / q = 3 : 3/4 = 3 * 4/3 = 4

y2 * y5 = 27/16 * 4 = 27/4