We have,
log2x(x2−5x+6)>1
f(x)=log2x(x2−5x+6)
At x=2,3,5, we get f(x)<1
When x=7,
f(7)=log2×7(72−5×7+6)
f(7)=log1420
f(7)=1.53
f(7)>1
Hence, the smallest prime number is 7.