a的x次方×ln(a)-b=0，解x 要过程谢谢 （a^x）*Ina-a=0,求x。详细过程
limx\u21920 (a^x-b^x)/x \uff01\uff01\u9ad8\u624b\u6c42\u89e3\uff01\uff01\u6025\u6025\u6025~~\u539f\u5f0f=lim x\u21920((a^x - 1) - (b^x - 1))/x
=lim x\u21920(a^x - 1)/x - lim x\u21920(b^x - 1)/x
=ln a - ln b (\u7531\u7b2c\u4e8c\u91cd\u8981\u6781\u9650\u63a8\u8bba\u53ef\u5f97)
=ln a/b
a^x\u00b7lna-a=0
a^x\u00b7lna=a
a^(x-1)\u00b7lna=1
a^(x-1)=loga(e)
loga[a^(x-1)]=loga[loga(e)]
x-1=loga[loga(e)]
x=1+ loga[loga(e)]
a^x =b/ln(a)
x=ln(b/ln(a))/lna
绛旓細鍥炵瓟锛歛^x =b/ln(a) x=ln(b/ln(a))/lna
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