{a3=a1×q∧²=3/2①S3=a1(1-q∧³)/1-q=9/2②一定要详细过程谢谢,
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/30 05:42:54
![{a3=a1×q∧²=3/2①S3=a1(1-q∧³)/1-q=9/2②一定要详细过程谢谢,](/uploads/image/z/10399821-69-1.jpg?t=%EF%BD%9Ba3%3Da1%C3%97q%E2%88%A7%26%23178%3B%3D3%2F2%E2%91%A0S3%3Da1%EF%BC%881-q%E2%88%A7%26%23179%3B%EF%BC%89%2F1-q%3D9%2F2%E2%91%A1%E4%B8%80%E5%AE%9A%E8%A6%81%E8%AF%A6%E7%BB%86%E8%BF%87%E7%A8%8B%E8%B0%A2%E8%B0%A2%2C)
{a3=a1×q∧²=3/2①S3=a1(1-q∧³)/1-q=9/2②一定要详细过程谢谢,
{a3=a1×q∧²=3/2①S3=a1(1-q∧³)/1-q=9/2②一定要详细过程谢谢,
{a3=a1×q∧²=3/2①S3=a1(1-q∧³)/1-q=9/2②一定要详细过程谢谢,
s3=a1+a2+a3=4.5,a3=a1*q*q=1.5,a1+a2=a1+a1*q=4.5-1.5=3,a1+a1*q=2*a3=2*a1*q*q,
约掉a1得1+q=2q*q,解得q=1,q=-0.5,