设lg2=a，lg3=b，那么lg1.8

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lg1.8======以下答案可供参考======
供参考答案1:
lg根号1.8
=lg1.8^(1/2)
=(1/2)lg1.8
=(1/2)(lg18-lg10)
=(1/2)(lg(2×3×3)-lg10)
=(1/2)(lg2+lg3+lg3-lg10)
=(1/2)(a+b+b-1)
=(a+2b-1)/2
供参考答案2:
lg根号1.8
=lg1.8^(1/2)
=(1/2)*lg(18/10)
=(1/2)(lg18-lg10)
=(1/2)(lg3^2*2-1)
=(1/2)(lg3^2+lg2-1)
=(1/2)(2*lg3+lg2-1)
=(2b+a-1)/2