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](/uploads/image/z/3691713-57-3.jpg?t=%E8%8B%A5%E7%AD%89%E6%AF%94%E6%95%B0%E5%88%97an%E6%BB%A1%E8%B6%B3a1%3D8%2Ca2a3%3D-8%2C%E5%88%99a3%2Ba4%E7%AD%89%E4%BA%8E)
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