求值:log2 (5/56)^(1/2)+log2 (14)-(1/2)log2 (35)=log2中2为底数=1/2[-2log2 (7)-3]+log2 (2)+log2 (7) 中的1/2[-2log2 (7)-3]是怎么得到的?

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求值:log2(5/56)^(1/2)+log2(14)-(1/2)log2(35)=log2中2为底数=1/2[-2log2(7)-3]+log2(2)+log2(7)中的1/2[-2log2(7)

求值:log2 (5/56)^(1/2)+log2 (14)-(1/2)log2 (35)=log2中2为底数=1/2[-2log2 (7)-3]+log2 (2)+log2 (7) 中的1/2[-2log2 (7)-3]是怎么得到的?
求值:log2 (5/56)^(1/2)+log2 (14)-(1/2)log2 (35)=
log2中2为底数
=1/2[-2log2 (7)-3]+log2 (2)+log2 (7) 中的1/2[-2log2 (7)-3]是怎么得到的?

求值:log2 (5/56)^(1/2)+log2 (14)-(1/2)log2 (35)=log2中2为底数=1/2[-2log2 (7)-3]+log2 (2)+log2 (7) 中的1/2[-2log2 (7)-3]是怎么得到的?
既然问道我了,就再写详细些:
=1/2(log2 [7^(-2)*2^(-3)]+log2(2*7)
=1/2[(log2 7^(-2)+log2 2^(-3)]+log2 (2*7)
=1/2log2 7^(-2)+1/2log2 2^(-3)]+log2 (2*7)
=1/2*2*log2 7+1/2*(-3)log2 2+log2 (2*7)
=1/2[-2log2 (7)-3]+log2 (2)+log2 (7)
log2 (5/56)^(1/2)+log2 (14)-(1/2)log2 (35)
=1/2log2 (5/56)-1/2log2 (35)+log2 (14)
=1/2[log2 (5/56/35)]+log2 (14)
=1/2log2 [1/(7^2*8)]+log2 (14)
=1/2(log2 [7^(-2)*2^(-3)]+log2(2*7)
=1/2[-2log2 (7)-3]+log2 (2)+log2 (7)
=-log2 (7)-3/2+1+log2 (7)
=-1/2

log2 (5/56)^(1/2)+log2 (14)-(1/2)log2 (35)
=-1/2

mi