(1)2log5*10+log5*0.25(2)log2(log2*16)(3)lg12.5-lg5/8+lg0.5第三题:y=√(x²+3x+2)+log2*3x的定义域是?

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(1)2log5*10+log5*0.25(2)log2(log2*16)(3)lg12.5-lg5/8+lg0.5第三题:y=√(x²+3x+2)+log2*3x的定义域是?(1)2log

(1)2log5*10+log5*0.25(2)log2(log2*16)(3)lg12.5-lg5/8+lg0.5第三题:y=√(x²+3x+2)+log2*3x的定义域是?
(1)2log5*10+log5*0.25
(2)log2(log2*16)
(3)lg12.5-lg5/8+lg0.5
第三题:y=√(x²+3x+2)+log2*3x的定义域是?

(1)2log5*10+log5*0.25(2)log2(log2*16)(3)lg12.5-lg5/8+lg0.5第三题:y=√(x²+3x+2)+log2*3x的定义域是?
(1)2log5*10+log5*0.25
=log5*10²+log5*0.25
=log5*(10²×0.25)
=log5*25
=log5*5²
=2
(2)log2(log2*16)
=log2*(log2*2^4)
=log2*4
=log2*2²
=2
(3)lg12.5-lg5/8+lg0.5
=lg(12.5×5/8×0.5)
=lg10
=1
第三题:y=√(x²+3x+2)+log2*3x的定义域是?
根号下大于等于0,真数大于0
所以x²+3x+2=(x+1)(x+2)≥0
x≤-2,x≥-1
3x>0
x>0
所以定义域(0,+∞)

1. 2Log5*10 + Log5*0.25 = log5*(10^2) + Log5*0.25 = Log5(100*0.25)
=Log5*25 = 2
2. log2(log2*16) = log2(4) = 2
3. lg12.5 - lg5/5 + lg0.5 = lg(12.5/(5/8)*0.5) = lg100 = 2