Log(0,5)4x=log(0,5)x+log(0,5)4=log(0,5)x-2
log(2)(x²/8)=log(20x²-log(2)8=2log(2)x-3=log(0,5)x/log(0,5)2 -3=-2log(0,5)x-3
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(log(0,5)-2)²-2log(0,5)x-3-8=0
log²(0,5)x-4log(0,5)x+4-2log(0,5)x-11=0
log²(0,5)x-6log(0,5)x-7=0
log(0,5)x=a
a²-6a-7=0
a1+a2=6 U a18a2=-7
a1=7⇒log(0,5)x=7⇒x=1/128
a2=-1⇒log(0,50x=-1⇒x=2