∵cos2χ=1-2sin²x
∴sin²x=½﹙1-cos2χ﹚
又sinxcosx=½sin2x
f(x)=sinx ^2+sinxcosx
=½﹙1-cos2χ﹚ +½sin2x
=½sin2x-½cos2χ+½
=√2/2sin﹙2x-π/4﹚+½
∴其最小正周期2π/2=π
∵0≤x≤π/2
∴-π/4≦2x-π/4≦3π/4
-1/√2≦2sin﹙2x-π/4﹚≦1
∴0≦√2/2sin﹙2x-π/4﹚+½≦√2/2+½
∴f﹙x﹚的最大值为√2/2+½
2x-π/4=π/2 x=3π/8
f﹙x﹚的最小值为0
∴-π/4=2x-π/4
x=0