1/(1-cos theta +2i sin theta) please convert it in x+iy form Share with your friends Share 0 Sandeep Saurav answered this Dear Student, To Express : 11-cosθ+2isinθ as x+iysolution : 1(1-cosθ)+2isinθ×(1-cosθ)-2isinθ(1-cosθ)-2isinθ=(1-cosθ)-2isinθ(1-cosθ)2-(2isinθ)2=(1-cosθ)-2isinθ(12+cos2θ -2cosθ)-(22i2sin2θ)=(1-cosθ)-2isinθ1+cos2θ -2cosθ+4sin2θ=(1-cosθ)-2isinθ1+cos2θ+sin2θ-2cosθ+3sin2θ=(1-cosθ)-2isinθ2-2cosθ+3sin2θ=1-cosθ2-2cosθ+3sin2θ+i-2sinθ2-2cosθ+3sin2θNote : Here, it is not give to use "a cosθ+i a sinθ⇒x2+y2=a and θ=tan-1yx". We only have to express as real terms seperate and imaginary terms seperate that's it.So, comapring above expression with x+iy⇒x=1-cosθ2-2cosθ+3sin2θ and y=-2sinθ2-2cosθ+3sin2θHence, 11-cosθ+2isinθ can be expressed as 1-cosθ2-2cosθ+3sin2θ+i-2sinθ2-2cosθ+3sin2θ as x+iy form. Hope this information will clear your doubts about topic. If you have any more doubts just ask here on the forum and our experts will try to help you out as soon as possible. Keep posting!! Regards 1 View Full Answer