令f(x)=(sinx-1)/(cosx-2)=t则sinx-1=t(cosx-2)sinx-tcosx=1-2t所以|1-2t|≤√(t^2+1)(1-2t)
令f(x)=(sinx-1)/(cosx-2)=t则sinx-1=t(cosx-2)sinx-tcosx=1-2t所以|1-2t|≤√(t^2+1)(1-2t)^2≤t^2+11-4t+4t^2≤t^2+13t^2-4t≤00≤t≤4/3本回答被提问者采纳
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令f(x)=(sinx-1)/(cosx-2)=t
则sinx-1=t(cosx-2)
sinx-tcosx=1-2t
所以|1-2t|≤√(t^2+1)
(1-2t)^2≤t^2+1
1-4t+4t^2≤t^2+1
3t^2-4t≤0
0≤t≤4/3本回答被提问者采纳