" 19.If "a=(cos theta+i sin theta)," prove that "(1+a)/(1-a)=(cot(theta)/(2))" i."

If a=cos theta+i sin theta, then (1+a)/(1-a) is equal to ( i) cot((theta)/(2))( ii) cot theta( iii) i cot((theta)/(2))( iv )i tan((theta)/(2))

If a=cos theta+i sin theta, then (1+a)/(1-a)=(cot theta)/(2) b.cot theta c.i(cot theta)/(2)d*i(tan theta)/(2)

Prove that (1+cos theta)/(sin theta)=cot[(theta)/(2)]

If alpha=cos theta+i sin theta, then (1+alpha)/(1-alpha) equals ( (i)cot theta(ii)i tan((theta)/(2))(iii)i cot((theta)/(2))(iv)cot((theta)/(2))

Prove that sin(2theta)/(1-cos2theta)=cot theta

Prove that : (1-cos theta+i sin theta)/(1+i sin theta+cos theta)=ie^(-1)tan((theta)/(2))

Prove that: (sin2 theta)/(1-cos2 theta)=cot theta

(1+cos theta+i sin theta)^(10)+(1+cos theta-i sin theta)^(10)=

Prove: (1+cos theta-sin^(2)theta)/(sin theta(1+cos theta))=cot theta

Show that ((1 + cos theta - sin ^(2) theta)/( sin theta (1 + cos theta ))) = cot theta