an = a1 + (n-1)d bn = b1×d^(n-1) a1 = b1 a4 = b4 所以 a1+3d = b1*d^3 (1) a10 = b10 所以 a1+9d = b1*d^9 (2) 两式相减:6d = b1(d^3-d^9) a1=b1=6d/(d^3-d^9) 代入 (1)或(2) a1=2^(1/3) d=-2^(1/3)
等差数列{an}的公差和等比数列{bn}的公比都是d,且a1=b1,a4=b4,a10=b10(1、4、10均为项数)
1个回答
相关问题
-
已知:等差数列{an}的公差和等比数列{bn}的公比都是d,(d≠1)且a1=b1,a4=b4,a10=b10;
-
已知,等差数列{an}的公差和等比数列{bn}的公比都是d(d≠1),a1=b1,a4=b4,a10=b10.
-
1``已知等差数列{An}的公差和等比数列{Bn}的公比都是d(d不为0)且a1=b1,a4=b4,a10=b10.
-
设等差数列{an}的公差与等比数列{bn}的公比都是d,d≠1,a1=b1,a4=b4,a10=b10
-
已知等差数列{an}的公差和等比数列{bn}的公比都是d,又知d≠1,且a4=b4,a10=b10
-
等差数列{an}等比数列{bn}其中a1=b1 a2=b2 a4=b4 两数列公差公比都为d 求{an}{bn}
-
设等差数列an的公差和等比数列bn的公比=d,a1=b1,a2=b2,a4=b4
-
已知等差数列{an}的公差和等比数列{bn}的公比是同一个非零实数d,且a1=b1,a4=b4,
-
设{an}是一个公差为d的等差数列,d≠0,前10项和S10=110,且a1,a2,a4成等比数列.若b1=a1,b(n
-
在等差数列{an}和等比数列{bn}中,a1=b1=1,b4=8,{an}的前10项和S10=55.