sin(2x) = 2sinxcosx
Euler's formula states that eθi=cosθ+i*sinθ. We can square both sides to get e2θi=cos2θ-sin2θ+i*2sinθcosθ. But we also know that e2θi=cos(2θ)+i*sin(2θ) (by applying Euler's formula to...
sin 2θ = 2(sin θ)(cos θ)cos 2θ = (cos θ)2 - (sin θ)2 cos 2θ = 2(cos θ)2 - 1 cos 2θ = 1 - 2(sin θ)2tan 2θ = 2(tan θ)/[1 - (tan θ)2] sin θ/2 = ±√[(1 - (cos θ))/2]cos θ/2 = ±√[(1 +...
The angle is 120°. Its supplement is 60°.
That depends what you want to calculate.
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