等比数列{an}中,a7*a11=6,a4+a14=5,则a20/a10=?

Question

等比数列{an}中,a7*a11=6,a4+a14=5,则a20/a10=?

Answer 1

∵为等比数列
∴a7*a11=a4*a14＝6且a4+a14＝5
即 a4=3,a14=2或a14=3,a4=2
∵a20/a10=10q且a14/a4=10q
∴a20/a10＝2/3或3/2