π<=x<=2π时 sinx<0 不满足;0<=x<=π/2时,sinx单调递增,且sin(π/6)=1/2,故π/6<=x<=π/2;又sinx在【0,π】上的函数图象关于π/2对称,故由对称性知x取值范围为【【π/6,5π/6】。综上,知x取值范围为【【π/6,5π/6】。 (纯手打)
解:∵sinπ/6=sin(π-π/6)=1/2又sinx≥1/2,∴π/6≤x≤π-π/6,即:π/6≤x≤5π/6
sinπ/6=sin5π/6=1/2π/6<=x<=5π/6