中科新闻网汉服与臃肿体型:一道高一数学简单的题目,谢谢大家！
来源：百度文库 编辑：中科新闻网 时间：2024/05/09 13:47:49
（x/9）^log[7]9=x/7
（x/9）^log[7]9=x/7
log[7]9*log[7]x/9=log[7]x/7
log[7]9{log[7]x-log[7]9}=log[7]x-log[7]7
log[7]9*log[7]x-log^2[7]9}=log[7]x-1
{log[7]9-1}*log[7]x=log^2[7]9-1
{log[7]9-1}*log[7]x={log[7]9-1}{log[7]9+1}
log[7]x=log[7]9+1
log[7]x=log[7]9+log[7]7=log[7]63
x=63