设a1,a2,a3成等差数列且a2=2令bn=2的an次方(n=1,2,3),则b1·b3= 过程
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设a1,a2,a3成等差数列且a2=2令bn=2的an次方(n=1,2,3),则b1·b3= 过程
![设a1,a2,a3成等差数列且a2=2令bn=2的an次方(n=1,2,3),则b1·b3= 过程](/uploads/image/z/16227486-54-6.jpg?t=%E8%AE%BEa1%2Ca2%2Ca3%E6%88%90%E7%AD%89%E5%B7%AE%E6%95%B0%E5%88%97%E4%B8%94a2%3D2%E4%BB%A4bn%3D2%E7%9A%84an%E6%AC%A1%E6%96%B9%28n%3D1%2C2%2C3%29%2C%E5%88%99b1%C2%B7b3%3D+%E8%BF%87%E7%A8%8B)
楼主的问题没写出符号, 应该是b1*b3吧?解如下
b1= 2^a1 b3=2^a3
所以 b1*b3= 2^a1 * 2^a3= 2^(a1+a3)= 2^(2*a2)= 2^4=16
b1= 2^a1 b3=2^a3
所以 b1*b3= 2^a1 * 2^a3= 2^(a1+a3)= 2^(2*a2)= 2^4=16
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