等比数列Bn,B5+B6=B7-B5=48,求S10=?答案是1023

来源:学生作业帮助网 编辑:作业帮 时间:2024/07/18 03:53:51
等比数列Bn,B5+B6=B7-B5=48,求S10=?答案是1023
x){)Ϧnx1)OT\BƦ`C[k<[lzC#c"}ِo#Bӎt$Lm8( y|}Ӂ* m` m 餞k +86PP0./VDk$ف<2}

等比数列Bn,B5+B6=B7-B5=48,求S10=?答案是1023
等比数列Bn,B5+B6=B7-B5=48,求S10=?答案是1023

等比数列Bn,B5+B6=B7-B5=48,求S10=?答案是1023
B5+B6=B7-B5=48
则有B5+B5Q=B5Q^2-B5
解得B5=16 Q=2
则A1=1
等比求和公式S10=1023
Sn=[A1(1-q^n]/(1-q)