f(x)=sin^2wx-cos^2wx(w>0)
=-cos2wx
f(x)最小正周期T=2π/(2w)=2π
∴w=1/2
(2)
f(x)=-cosx
∵tanx=4/3,x属于(0,π/2)
∴{sinx/cosx=4/3
{sin^2x+cos^2x=1
{sinx>0,cosx>0
解得:cosx=3/5
∴f(x)=-cosx=-3/5
f(x)=sin^2wx-cos^2wx(w>0)
=-cos2wx
f(x)最小正周期T=2π/(2w)=2π
∴w=1/2
(2)
f(x)=-cosx
∵tanx=4/3,x属于(0,π/2)
∴{sinx/cosx=4/3
{sin^2x+cos^2x=1
{sinx>0,cosx>0
解得:cosx=3/5
∴f(x)=-cosx=-3/5