解方程:x的log以2为底x的对数=32x的4次
问题描述:
解方程:x的log以2为底x的对数=32x的4次
答
x^[log2(x) -4]=32x^4x^[log2(x) -4]=2^5log2(x) -4=log2(2^5) / log2(x) =5/log2(x)[log2(x)]^2 -4log2(x) -5=0[log2(x) -5][log2(x) +1] =0log2(x) =5 ====> x=2^5或者log2(x)=-1 ====> x=1/2