函数y=1/2 sin2x+sin^2x x属于R的值域是—rt_数学解答

函数y=1/2 sin2x+sin^2x x属于R的值域是—
rt

人气：383 ℃　时间：2019-10-08 16:43:08

解答

y=1/2sin2x+(1-cos2x)/2
=1/2(sin2x-cos2x)+1/2
=√2/2*(√2/2*sin2x+√2/2zos2x)+1/2
=√2/2*(sin2xzosπ/4+cos2xsinπ/4)+1/2
=√2/2*sin(2x+π/4)+1/2
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