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log2根下7/48+log212-1/2log2421/2lg32/49-4/3lg根下8+lg根下245
题目详情
log2根下7/48+log212-1/2log242
1/2lg32/49-4/3lg根下8+lg根下245
1/2lg32/49-4/3lg根下8+lg根下245
▼优质解答
答案和解析
log2[根号下(7/48)]+log2(12)-1/2log2(42)-1?
=log2{12*根号下(7/48)/[根号下(42)]}-1
=log2{12*根号下[7/(48*42)]}-1
=log2{12*根号下[7/(6*2*2*2**6*7)]}-1
=log2根号下(1/2)-1
=(1/2)log2(1/2)-1
=(1/2)log2(2^-1)-1
=(-1)(1/2)log2(2)-1
=-1/2-1
=-3/2
=log2{12*根号下(7/48)/[根号下(42)]}-1
=log2{12*根号下[7/(48*42)]}-1
=log2{12*根号下[7/(6*2*2*2**6*7)]}-1
=log2根号下(1/2)-1
=(1/2)log2(1/2)-1
=(1/2)log2(2^-1)-1
=(-1)(1/2)log2(2)-1
=-1/2-1
=-3/2
看了 log2根下7/48+log...的网友还看了以下：