sin374°cos148°+sin77°cos58° 和sin(a+b)cos(γ-b)-cos(b+a)sin(b-γ)
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sin374°cos148°+sin77°cos58° 和sin(a+b)cos(γ-b)-cos(b+a)sin(b-γ)
sin374°cos148°+sin77°cos58° 和sin(a+b)cos(γ-b)-cos(b+a)sin(b-γ)
sin374°cos148°+sin77°cos58° 和sin(a+b)cos(γ-b)-cos(b+a)sin(b-γ)
1
sin347°cos148°+sin77°cos58°
=sin13°cos32°+cos13°sin32°
=sin(13+32)°
=sin45°
=√2/2
2
sin(a+b)cos(γ-b)-cos(b+a)sin(b-γ)
=sin(a+b)cos(γ-b)+cos(a+b)sin(γ-b)
=sin(a+b+b-y)
=sin(a-y)
sin(a+b)cos(γ-b)-cos(b+a)sin(b-γ)=sin(a+b)cos(γ-b)+cos(a+b)sin(y-b)=
=sin((a+b)+(γ-b))
=sin(a+y)
1 sin347°cos148°+sin77°cos58°
=_sin13°cos32°+cos13°sin32°
=-sin(13-32)°
=-s...
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sin(a+b)cos(γ-b)-cos(b+a)sin(b-γ)=sin(a+b)cos(γ-b)+cos(a+b)sin(y-b)=
=sin((a+b)+(γ-b))
=sin(a+y)
1 sin347°cos148°+sin77°cos58°
=_sin13°cos32°+cos13°sin32°
=-sin(13-32)°
=-sin(-19)°
=sin19°
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