数列 {a_n }满足:a_1=a,a_(n+1)=√(a_(n+3)/2),n=1,2,3,.(1)若数a_(n+1)=a_n,求a的值;(2)若a=1/2时数列 {a_n }满足:a_1=a,a_(n+1)=√(a_n +3)/2),n=1,2,3,.(1)若数a_(n+1)=a_n,求a的值;(2)若a=1/2时,证明:a_n<3/2(n=1,
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数列 {a_n }满足:a_1=a,a_(n+1)=√(a_(n+3)/2),n=1,2,3,.(1)若数a_(n+1)=a_n,求a的值;(2)若a=1/2时数列 {a_n }满足:a_1=a,a_(n+1)=√(a_n +3)/2),n=1,2,3,.(1)若数a_(n+1)=a_n,求a的值;(2)若a=1/2时,证明:a_n<3/2(n=1,
数列 {a_n }满足:a_1=a,a_(n+1)=√(a_(n+3)/2),n=1,2,3,.(1)若数a_(n+1)=a_n,求a的值;(2)若a=1/2时
数列 {a_n }满足:a_1=a,a_(n+1)=√(a_n +3)/2),n=1,2,3,.(1)若数a_(n+1)=a_n,求a的值;(2)若a=1/2时,证明:a_n<3/2(n=1,2,3,...)(3)设数列{a_n-1 }的前n项之积为T_n,若对任意正整数n总有(a_n-1)T_n≤6,求a的取值范围
数列 {a_n }满足:a_1=a,a_(n+1)=√(a_(n+3)/2),n=1,2,3,.(1)若数a_(n+1)=a_n,求a的值;(2)若a=1/2时数列 {a_n }满足:a_1=a,a_(n+1)=√(a_n +3)/2),n=1,2,3,.(1)若数a_(n+1)=a_n,求a的值;(2)若a=1/2时,证明:a_n<3/2(n=1,
我晕了,你这说的完全不一样:a_(n+1)=√(a_(n+3)/2),a_(n+1)=√(a_n +3)/2)
这明显有问题嘛,我估计是后面的吧,我就做后面的了
(1)a(n+1)=√【(an +3)/2】,若a(n+1)=a(n) 直接解方程 2a^2 = a +3 因式分解就可以得出结果
(2)用数学归纳法证明:
当 n = 1 时 a1 = 1/2
当 n = 2 时 a2 = √[(an +3)/2] < √(3+ 1/2) /2 = √7/4 < 3/2
假设党n = k时候a(n)<3/2
则 n = k+1 时 a(n+1)=√【(an +3)/2】< a(n+1)=√【(3/2 +3)/2】= 3/2
即当 n = k+1 时 a(n+1)< 3/2 成立,故假设成立,即命题得证.
(3) 这问有点麻烦,没时间了,要吃饭了,不好意思了.我看下午给你答案.