已知函数f(x)=sinxcosx+sin²x 求f(0)和f(π/2)的值

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已知函数f(x)=sinxcosx+sin²x 求f(0)和f(π/2)的值
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已知函数f(x)=sinxcosx+sin²x 求f(0)和f(π/2)的值
已知函数f(x)=sinxcosx+sin²x 求f(0)和f(π/2)的值

已知函数f(x)=sinxcosx+sin²x 求f(0)和f(π/2)的值
f(x)=sinxcosx+sin²x
=1/2sin2x+(1-cos2x)/2
=1/2sin2x-1/2cos2x+1/2
=√2/2*(√2/2sin2x-√2/2cos2x)+1/2
=√2/2*sin(2x-π/4)+1/2
f(0)=√2/2*sin(2*0-π/4)+1/2
=√2/2*sin(-π/4)+1/2
=-√2/2*sinπ/4+1/2
=-√2/2*√2/2+1/2
=-1/2+1/2
=0
f(π/2)=√2/2*sin(2*π/2-π/4)+1/2
=√2/2*sin(π-π/4)+1/2
=√2/2*sinπ/4+1/2
=√2/2*√2/2+1/2
=1/2+1/2
=1

f(x)=sinxcosx+sin²x . f(0)=0 , f(π/2)=1

直接带入不就行了

不求f(x)直接 带入

f(0)=0 f(π/2)=1