函数f（x）=根号-x^2+x+6/x-1的定义域为

函数f（x）=根号-x^2+x+6/x-1的定义域为
函数f（x）=根号-x^2+x+6/x-1的定义域为

函数f（x）=根号-x^2+x+6/x-1的定义域为
根号下大于等于0
-x²+x+6>=0
x²-x-6<=0
(x-3)(x+2)<=0
-2<=x<=3
分母不等于0
x-1≠0
x≠1
所以定义域[-2,1)∪(1,3]

cos(x-π/4)
=cosxcosπ/4+sinxsinπ/4
=√2/2*(cosx+sinx)=√2/10
sinx+cosx=1/5
cosx=1/5-sinx
平方
cos²x=1-sin²x=1/25-2/5*sinx+sin²x
sin²x-1/5*sinx-12/25=0
(s...

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cos(x-π/4)
=cosxcosπ/4+sinxsinπ/4
=√2/2*(cosx+sinx)=√2/10
sinx+cosx=1/5
cosx=1/5-sinx
平方
cos²x=1-sin²x=1/25-2/5*sinx+sin²x
sin²x-1/5*sinx-12/25=0
(sinx-4/5)(sinx+3/5)=0
由x范围
sinx>0
sinx=4/5
cosx=1/5-sinx=-3/5
sin2x=2sinxcosx=-24/25
cos2x=cos²x-sin²x=-7/25
sin(2x+π/3)
=sin2xcosπ/3+cos2xsinπ/3
=-(24+7√3)/50

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