Răspuns:
x∈∅
Explicație pas cu pas:
9-4√5=2²+(√5)²-2*2*√5=(2-√5)²
x√(2-√5)²≤3√5-6
x|2-√5|≤3√5-6
x(√5-2)≤3√5-6
impartim cu √5-2>0, ineg.se pastreaza
x/(3√5-6)/(√5-2)
x≤(√5+2)(3√5+6)/(9-4)
x≤(15+12+6√5+6√5)/6
x≤(18+12√5)/6
x≤3+2√5
cum 2√5∈(√16; √25)=(4;5)
x≤3+2*4=8
deci x∈{1;2...8}
