0.5lg32/49 - 4/3lg√8+lg√245

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0.5lg32/49 - 4/3lg√8+lg√245

0.5lg32/49 - 4/3lg√8+lg√245
0.5lg32/49 - 4/3lg√8+lg√245

0.5lg32/49 - 4/3lg√8+lg√245
=lg(32/49)^(1/2)-lg[2^(3/2)]^(4/3)+lg√245
=lg(4√2/7)-lg(2^2)+lg7√5
=lg[(4√2/7)÷4×7√5)]
=lg√10
==lg10^(1/2)
=1/2

0.5lg32/49 - 4/3lg√8+lg√245
=0.5(lg2^5-lg7^2)-(4/3)*(1/2)lg2^3+(1/2)lg(5*7^2)
=0.5*5*lg2-0.5*2*log7-(4/3)*(1/2)*3lg2+0.5*lg5+0.5*2log7
=(2.5-2)lg2+(-1+1)log7+0.5lg5
=0.5lg2+0.5lg5
=0.5lg(2*5)
=0.5