lim lncos3x÷lncos4x=lim (-3sin3x/cos3x)÷(-4sin4x/cos4x)=lim (3sin3x)/(4sin4x)=lim (9cos3x)/(16cos4x)=9/16
lim(x→0)lncos3x÷lncos4x=lim(x→0)(-3sin3x/cos3x)/(-4sin4x/cos4x)=lim(x→0)(3sin3x)/(4sin4x)=lim(x→0)(9cos3x)/(16cos4x)=9/16