y=sinx/2+cosx/2在(-2π,2π)内的递增区间为多少?答案是-3/2π

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y=sinx/2+cosx/2在(-2π,2π)内的递增区间为多少?答案是-3/2π
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y=sinx/2+cosx/2在(-2π,2π)内的递增区间为多少?答案是-3/2π
y=sinx/2+cosx/2在(-2π,2π)内的递增区间为多少?答案是-3/2π<=x<=π/2
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y=sinx/2+cosx/2在(-2π,2π)内的递增区间为多少?答案是-3/2π
asinx+bcosx=√(a^2+b^2)*sin(x+z)
其中tanz=b/a
所以y=√2sin(x/2+π/4)
-2π所以-π-3π/4sin增区间是[2kπ-π/2,2kπ+π/2]
-3π/4-π/2<=x/2+π/4<=π/2
-3π/4<=x/2<=π/4
-3π/2<=x<=π/2

y=根号2*sin(x/2+π/4) 所以,递增的区间应该是满足: 2kπ-π/2<=x/2+π/4<=2kπ+π/2的x. 在[-2π,2π]上,就是: [-2π,-3π/2],[-π/2,π/2],[3π/2,2π].