1
log(2)x=log(2)15
x=15
2
x²-11x+27>0
D=121-108=13
x1=(11-√13)/2 U x2=(11+√13)/2
x∈(-∞;(11-√13)/2 U ((11+√13)/2;∞)
x²-11x+27=9
x²-11x+18=0
x1*x2=11 U x1*x2=18
x1=2 U x2=9
3
x²+x-5>0
D=1+20=21
x1=(-1-√21)/2 U x2=(-1+√21)/2
x∈(-∞;(-1-√21)/2) U ((-1+√21)/2;∞)
x²+x-5=7
x²+x-12=0
x1+x2=-1 U x1*x2=-12
x1=-4 U x2=3
4
x>0
log(0,3)x=a
2a²-7a-4=0
D=49+32=81
a1=(7-9)/4=-1/2⇒log(0,3)x=-1/2⇒x=√(10/3)=√30/3
a2=(7+9)/4=4⇒log(0,3)x=4⇒x=(0,3)^4=0,0081
5
x>0
log(1/2)x=a
3a²+5a-2=0
D=25+24=49
a1=(-5-7)/6=-2⇒log(1/2)x=-2⇒x=4
a2=(-5+7)/6=1/3⇒log(1/2)x=1/3⇒x=1/∛2