若等比数列an满足a1=8,a2a3=-8,则a3+a4等于

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若等比数列an满足a1=8,a2a3=-8,则a3+a4等于

若等比数列an满足a1=8,a2a3=-8,则a3+a4等于
若等比数列an满足a1=8,a2a3=-8,则a3+a4等于

若等比数列an满足a1=8,a2a3=-8,则a3+a4等于
a2a3
=a1q*a1q^2
=a1^2q^3=-8
q^3=-8/8^2=-1/8
q=-1/2
则 a3+a4=a1q^2+a1q^3=2-1=1

你这道题有问题~没法解答

a1/a2=a2/a3
8a3=a2*a2
a3=2
a2=-4
a4=-1