已知函数f(x)=Asin(x+ψ)(A〉0,0
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已知函数f(x)=Asin(x+ψ)(A〉0,0
已知函数f(x)=Asin(x+ψ)(A〉0,0
已知函数f(x)=Asin(x+ψ)(A〉0,0
f(x)=Asin(x+ψ) ,A=1 ,
x+ψ=2kπ+π/2
1/2=sin(π/3+ψ) ,π/3+ψ=2kπ+5π/6
ψ=π/2
f(x)=sin(x+π/2)
3/5=sin(a+π/2)=cosa ,sina=4/5
12/13=sin(b+π/2)=cosb ,sinb=5/13
f(a-b)=sin(a-b+π/2)=cos(a-b)
=cosacosb+sinasinb
=56/65
sin(A+B) = sinAcosB+cosAsinB
cos(A+B) = cosAcosB-sinAsinB
因为F(X)最大值为1且A>0,则A=1,
图像过M点,则ψ=-π/6,
则F(X)=sin(x-π/6).
f(b)=sin(b-π/6)=12/13
b=arcsin12/13+π/6
f(a-b)=sin(a-b-π/...
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sin(A+B) = sinAcosB+cosAsinB
cos(A+B) = cosAcosB-sinAsinB
因为F(X)最大值为1且A>0,则A=1,
图像过M点,则ψ=-π/6,
则F(X)=sin(x-π/6).
f(b)=sin(b-π/6)=12/13
b=arcsin12/13+π/6
f(a-b)=sin(a-b-π/6)=sin(a-π/6)cosb+sinbcos(a-π/6)=3/5cosb
+4/5cosb=3/5cos(arcsin12/13+π/6)+4/5sin(arcsin12/13+π/6)=3/5*(5/13)*{【根号3)/2】-(4/5)(12/13)*(1/2)=3(根号3)/26-24/65
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