Ответ:
125
Объяснение:
5(5а^(-3))^(-2) •а^(-2)=5•5^(-2) •а^6 •а^(-2)=5^(1-2) •а^(6-2)=5^(-1) •а^4=1/5 •а^4=0,2•(0,2^(-1))^4=0,2•0,2^(-4)=0,2^(1-4)=0,2^(-3)=1/0,2^3=1/0,008=1000/8=125
㏒ₐа⁶*b¹⁰=㏒ₐа⁶+㏒ₐb¹⁰=6㏒ₐа+10㏒ₐb=6+10*8=86
㏒ₐа⁶/b⁴=㏒ₐа⁶ -㏒ₐb⁴=6㏒ₐа -4㏒ₐb=6-4*(-2)=14
<span>cos17cos73=0.5(cos90+cos56)</span>
<span><span>sin13cos21=0.5(sin34-sin8)</span></span>
<span><span><span>cos4cos86=0.5(cos90+cos82)</span></span></span>
<span><span><span>cos90=0</span></span></span>
<span><span><span>cos56=cos(90-34)=sin34</span></span></span>
<span><span><span>cos82=cos(90-8)=sin8</span></span></span>
<span><span><span><span>cos17cos73-sin13cos21-cos4cos86=0.5(sin34-sin34+sin8-sin8)=0</span></span></span></span>
4lg|x|-lg²(-x)-4=0
-x>0 →x<0 |x|=-x
lg (-x)=t -t²+4t-4=0 t²-4t+4=(t-2)²=0 t=2
lg(-x)=2 -x=10²=100 x=-100