Prueba vectorial real de habilidades aritméticas orales
f(x)=2a*b-1
=2[√3sinxcosx+cos? x]-1
=(√3)sen2x+[1+cos2x]-1
= 2[(√3/2)sen2x+(1/2)cos2x]
= 2[sin 2 xcos(π/6)+cos 2 xsin(π/6)]
=2sin(2x+π/6)
Entonces :f(x)=1 es 2sen (2x+π/6) = 1.
sin(2x+π/6)=1/2
Porque x∈[π/6, π/2], entonces 2x+π/6 ∈ [π/2 , 7π/6], entonces: 2x+π/6 = 5π/6, entonces x=π/3.